Optical device

ABSTRACT

Stereoscopic device including an image directing assembly, an image differentiator and an image detector, the image directing assembly having a first light inlet for receiving a first image and a second light inlet for receiving a second image, the first light inlet being spaced apart from the second light inlet, the image differentiator differentiating between the first image and the second image, wherein the image directing assembly directs the first image to the image detector via a common path, and wherein the image directing assembly directs the second image to the image detector via the common path.

This application is a divisional of Ser. No. 10/145,418, filed May 13,2002, which is a continuation-in-part of application Ser. No.09/785,791, filed on Feb. 16, 2001 and Ser. No. 09/785,512, filed onFeb. 16, 2001, which are continuation-in-parts of application Ser. No.09/699,624, filed on Oct. 30, 2001, which is a continuation-in-part ofapplication Ser. No. 09/257,850, filed on Feb. 25, 1999 and whichapplication(s) are incorporated herein by reference.

FIELD OF THE DISCLOSED TECHNIQUE

The disclosed technique relates to endoscopes, microscopes andboroscopes, in general and to stereoscopic image pick up devices withcolor imaging capability, in particular.

BACKGROUND OF THE DISCLOSED TECHNIQUE

Stereoscopic image detection devices are known in the art. Such devicesare required to obtain and provide a combination of small cross sectionand high image quality. It will be appreciated by those skilled in theart that high image quality, in general, is characterized bystereoscopic vision accuracy, color capabilities, high resolution andillumination requirements.

It is noted that conventional methods, which provide stereoscopicimages, require a wider optical path than a monocular one. Such awidened optical path enlarges the cross-section required for thedetection device considerably. Hence, the requirement for a small crosssection is not maintained.

U.S. Pat. No. 5,527,263 to Zobel, et al., is directed to a dual opticalpath stereo endoscope with simple optical adjustment. U.S. Pat. No.5,776,049 to Takahashi, is directed to a “Stereo Endoscope and StereoEndoscope Imaging Apparatus” and provides a device which utilizes acombination of two optical paths with two charge coupled devices(CCD's), capable of variable zoom.

Auto-stereoscopic devices, which utilize one optical system to provide astereo effect, are also known in the art. Such a device is provided inU.S. Pat. No. 5,603,687 to Hori et al., which is directed to a devicewith two parallel optical axes and two CCD units. Hori selected anasymmetrical approach, wherein one optical channel has a large aperturefor light and details, and the other optical channel provides a parallaximage for stereoscopic imagery to the proximal CCD.

U.S. Pat. No. 5,613,936 to Czarnek et al., is directed to a stereoscopicendoscope device which utilizes light polarization and timemultiplexing, in order to transmit each different polarized imagecorresponding to left and right images multiplexed in time, through oneoptical channel that transfers images from the lateral side of theendoscope shaft. This endoscope has to be inserted deeper into the humancavity to receive a stereo image. It must also be used with a headmounted display device called “switched shutter glasses” that causes eyeirritation. It is noted that according to Czarnek each image is receivedin 25% of the original quality. As much as 50% of the light receivedfrom the object, is lost due to polarization considerations and as muchas 50% of the remaining information is lost due to channel switching.

U.S. Pat. No. 5,588,948, to Takahashi, et al., is directed to astereoscopic endoscope. The stereo effect is produced by having adividing pupil shutter, which splits the optical path onto the left andright sides, and the up and down sides. These sides are alternatelyprojected on a proximal image pick up device, using time multiplexing.According to another aspect of this reference, a distal CCD is included,which is divided to left and right sides with a shading memberseparating them, for achieving space multiplexing.

U.S. Pat. No. 5,743,847 to Nakamura et al., is directed to a“Stereoscopic Endoscope Having Image Transmitting Optical-System andPupil Dividing Unit that are Axially Movable With Respect to EachOther”, which uses a plural pupil dividing means and one opticalchannel. U.S. Pat. No. 5,751,341 to Chaleki et al., is directed to a“Stereoscopic Endoscope System”, which is basically a two channelendoscope, with one or two proximal image sensors. A rigid sheath withan angled distal tip could be attached to its edge and be rotated, forfull view.

U.S. Pat. No. 5,800,341 to Mckenna et al., is directed to an“Electronically Steerable Endoscope”, which provides different fields ofview, without having to move the endoscope, using a plurality of CCDcells and processing means. U.S. Pat. No. 5,825,534 to Strahle, isdirected to a “Stereo Endoscope having a Folded Sight Line” including astereo-endoscope optical channel, having a sight line folded relative totube axis.

U.S. Pat. No. 5,828,487 to Greening et al., is directed to a“Stereoscopic Viewing System Using a Two Dimensional Lens System” whichin general, provides an alternative R-L switching system. This systemuses a laterally moving opaque leaf, between the endoscope and thecamera, thus using one imaging system. U.S. Pat. No. 5,594,497 to Ahern,describes a distal color CCD, for monocular view in an elongated tube.

The above descriptions provide examples of auto-stereoscopic disclosedtechniques, using different switching techniques (Time divisionmultiplexing) and polarization of channels or pupil divisions (spatialmultiplexing), all in an elongated shaft. When color image pick updevices are used within these systems, the system suffers from reducedresolution, loss of time related information or a widened cross section.

The issue of color imagery or the issue of a shaft-less endoscope is notembedded into any solution. To offer higher flexibility and to reducemechanical and optical constraints it is desired to advance the imagepick-up device to the frontal part of the endoscope. This allows muchhigher articulation and lends itself easily to a flexible endoscope.Having a frontal pick up device compromises the resolution of the colordevice due to size constraints (at this time).

U.S. Pat. No. 5,076,687 to Adelson, is directed to an “Optical RangingApparatus” which is, in general a depth measuring device utilizing alenticular lens and a cluster of pixels.

U.S. Pat. No. 5,760,827 to Faris, is directed to “Pixel Data ProcessingSystem and Method for Producing Spectrally-Multiplexed Images ofThree-Dimensional Imagery for Use in Stereoscopic Viewing Thereof” anddemonstrates the use of multiplexing in color and as such, offers asolution for having a color stereo imagery with one sensor.Nevertheless, such a system requires several sequential passes to beacquired from the object, for creating a stereo color image.

U.S. Pat. No. 5,812,187 to Watanabe, is directed to an ElectronicEndoscope Apparatus. This device provides a multi-color image using amonochromatic detector and a mechanical multi-wavelength-illuminatingdevice. The monochromatic detector detects an image, each time themulti-wavelength-illuminating device produces light at a differentwavelength.

U.S. Pat. No. 6,306,082 B1 issued to Takahashi, et al., and entitled“Stereoendoscope wherein images having passed through plural incidentpupils are transmitted by common relay optical systems”, is directed toan apparatus, namely, an endoscope wherein images, having passed throughplural incident pupils, are transmitted by a common relay system, andreconstructed at an observation point to provide a streoscopic image.According to the reference, illuminating light is transmitted by a lightguide. Light reflected from the illuminated objects passes throughnon-superimposed pupils and transmitted to the rear side by a commonrelay system having a single optical axis. The transmitted images areformed on separate image taking surfaces to allow for a streoscopicimage to be formed.

U.S. Pat. No. 5,121,452 issued to Stowe, et al., and entitled “FiberOptic Power Splitter”, is directed to a method for manufacturing fiberoptic power splitters. The fiber optic power splitter is a unitary,single-mode fiber, fused structure which is composed of four, up toseventeen or more fibers, which provide uniform splitting of inputoptical power among the fibers. The fiber optic power splitter includesa central fiber and identical surrounding fibers, which are sized priorto fusion, such that mutual contact is achieved. In this manner, each ofthe surrounding fibers touches the central fiber and the neighboringfibers. In this construction, the surrounding fibers are of the samediameter and the central fiber has a different diameter. Optical powerinput in the central fiber distributes among the surrounding fibers. Theoptical power output in the central fiber and the surrounding fibers ismonitored during the fusion process, and the fusion process is stoppedwhen the desired fraction of the optical power appears in a surroundingfiber.

In Handbook of Optics, Volume 2, McGraw-Hill, Inc., 1995, p. 15-24,Norman Goldberg discusses the concept of stereo cameras. The structureof a stereo camera is based on the parallax difference between the viewsof the right and the left eyes. The two lenses in the classic stereocamera are spaced about 65 mm apart, in order to form two images of thesubject. Another type of stereo camera uses a reflection system of fourmirrors or an equivalent prism system, placed in front of the lens of anormal camera, thereby forming two images of the subject (FIG. 15 on p.15-25 of the Handbook). According to another method, the subject isrequired to remain stationary while two separate exposures are made andthe camera is shifted 65 mm between the two exposures. This method isemployed in aerial stereo photography in which two views are made of theground, the views being made so many seconds apart.

According to another method, the right and left views of the subject arerestricted to the respective eye of the viewer, where the right and theleft views are polarized at 90 degrees to one another. The viewer wearsglasses with polarizing filters oriented such that each eye sees theview intended for it. In a parallax stereogram, the right and leftimages are sliced into narrow, interlaced right and left strips. Theviewer perceives a three-dimensional view of the subject, while viewingthe image through a series of vertical lenticular prisms with a matchingpitch.

U.S. Pat. No. 5,233,416 issued to Inoue and entitled “ElectronicEndoscope System”, is directed to a system which enables the use of anendoscope having either a normal sensitivity or a high sensitivitysolid-state image sensor element. The system includes a rotary colorwheel, a light source, a condenser lens, the solid-state image sensorelement, such as charge coupled device (CCD), an input switch, a firstvideo processor, a second video processor, an output switch, an analogto digital (A/D) converter, a plurality of storage portions, threedigital to analog (D/A) converters, an encoder, a first control means, asecond control means, a decoder, a master clock and a CCD drive.

The CCD drive is coupled with the CCD, the first control means, and tothe master clock. The first control means is coupled with the inputswitch, the first video processor, the second video processor, theoutput switch, the A/D converter, the storage portions, the decoder andto the master clock. The CCD is coupled with the decoder and to theinput switch. The input switch is coupled with the first video processorand to the second video processor. The output switch is coupled with thefirst video processor, the second video processor and to the A/Dconverter. The storage portions are coupled with the A/D converter, tothe three D/A converters and to the second control means. The secondcontrol means is coupled with the decoder, the master clock, the D/Aconverters and to the encoder. The three D/A converters are coupled withthe encoder.

The condenser lens is located between the light source and the rotarycolor wheel. The rotary color wheel is located between the condenserlens and a light guide of the endoscope. The rotary color wheel isprovided with three filter zones (red, green and blue). The three filterzones are separated by three color-shifting light-blocking zones. Eachfilter zone is bisected into uniform halves, by an intermediatelight-blocking zone.

The input switch switches the system to the first video processor whenthe normal sensitivity CCD is employed and to the second videoprocessor, when the high sensitivity CCD is employed. The first controlmeans controls the read-out of the signal charges from the CCD and thesecond control means controls the display of the images. Each of thefirst control means and the second control means can operate either in anormal sensitivity mode or a high sensitivity mode. The CCD driveproduces pulse signals for the CCD, according to the clock signals ofthe master clock.

The rotary color wheel provides an image to the CCD in red, green andblue, in sequence. When a normal sensitivity CCD is employed, the systemswitches to the first video processor, and the first control means, thesecond control means and the CCD drive switch to the normal sensitivitymode. In this mode, the CCD drive enables the read-out of signal chargesfrom the CCD, between every two color-shifting light-blocking zones. Thefirst controller shifts the resulting image to the storage portions,during each color-shifting light-blocking zone. The second controllerconstructs a color image for each pulse signal, by combining the threeimages in red, green and blue which are read-out between every twocolor-shifting light-blocking zones.

When a high sensitivity CCD is employed, the system switches to thesecond video processor, and the first control means, the second controlmeans and the CCD drive switch to the high sensitivity mode. In thismode, the CCD drive enables the read-out of signal charges from the CCD,between every two color-shifting light-blocking zones, as well asbetween every two intermediate light-blocking zones. The firstcontroller shifts the resulting image to the storage portions, duringeach color-shifting light-blocking zone, as well as during eachintermediate light-blocking zone. The second controller constructs acolor image for each pulse signal, by combining the three images in red,green and blue which are read-out between every two color-shiftinglight-blocking zones, as well as between every two intermediatelight-blocking zones.

SUMMARY OF THE DISCLOSED TECHNIQUE

It is an object of the disclosed technique to provide a novel system forstereoscopic imaging, by employing an image receiving assembly whoseinlets are spaced apart, and a novel method for operating the same,which overcomes the disadvantages of the prior art.

In accordance with one aspect of the disclosed technique, there is thusprovided a stereoscopic device which includes an image directingassembly, an image differentiator and an image detector. The imagedirecting assembly includes a first light inlet for receiving a firstimage and a second light inlet for receiving a second image, wherein thefirst light inlet and the second light inlet are spaced apart. The imagedifferentiator differentiates between the first image and the secondimage and the image directing assembly directs the first image and thesecond image to the image detector via a common path.

A controller coupled with the image detector and to an image processor,enables the image detector to detect the first image and the secondimage according to the state of the image differentiator. The imageprocessor produces a stereoscopic image, by processing the detectedfirst image and second image.

In accordance with another aspect of the disclosed technique, there isthus provided a method for producing a stereoscopic image. The methodincludes the procedures of receiving images of different sides of anobject through two spaced apart apertures, directing the images to acommon path and differentiating between the images. The method furtherincludes the procedures of detecting the images, processing the detectedimages and displaying a stereoscopic image according to the processedimages.

In accordance with a further aspect of the disclosed technique, there isthus provided a stereoscopic device including a first light filter, asecond light filter, a sequential wavelength differentiator, an imagedetector and an optical assembly located in front of the image detector.The first light filter admits light at a plurality of first ranges offilter wavelengths and the second light filter admits light at aplurality of second ranges of filter wavelengths. The sequentialwavelength differentiator is associated with a first set ofdifferentiating wavelengths and with a second set of differentiatingwavelengths.

The image detector receives images from the first light filter and fromthe second light filter. The first set of differentiating wavelengths isincluded in at least one of the first ranges of filter wavelengths andexcluded from the second ranges of filter wavelengths. The second set ofdifferentiating wavelengths is included in at least one of the secondranges of filter wavelengths and excluded from the first ranges offilter wavelengths. A controller is coupled with the image detector, tothe image processor and to the sequential wavelength differentiator. Thecontroller enables the image detector to detect the first image and thesecond image according to the state of the sequential wavelengthdifferentiator. The image processor produces a stereoscopic image, byprocessing the detected first image and second image.

The sequential wavelength differentiator can be a sequentialilluminator, sequentially emitting light at least a portion of the firstset of differentiating wavelengths and at least a portion of the secondset of differentiating wavelengths. Alternatively, the sequentialwavelength differentiator can be a filtering differentiator,differentiating between at least a portion of the first ranges of filterwavelengths and at least a portion of the second ranges of filterwavelengths.

Further alternatively, the filtering differentiator can be amulti-wavelength rotating disk located in front of the image detector,wherein the multi-wavelength rotating disk includes a plurality offiltering sectors. Each of the filtering sectors admits light atdifferent wavelengths selected from one of the first set ofdifferentiating wavelengths and the second set of differentiatingwavelengths. The multi-wavelength rotating disk sequentially filterslight at the common path and the controller enables the image detectorto detect images, according to the angular position of themulti-wavelength rotating disk.

In accordance with another aspect of the disclosed technique, there isthus provided a method for detecting a first image and a second image.The method includes the procedure of determining a plurality of firstranges of filter wavelengths for a first pupil and a plurality of secondranges of filter wavelengths for a second pupil. The method furtherincludes the procedure of sequentially differentiating between a firstset of differentiating wavelengths and a second set of differentiatingwavelengths. The method includes still further, the procedure ofdetecting the first image when the first set of differentiatingwavelengths is present, and detecting the second image when the secondset of differentiating wavelengths is present. The first set ofdifferentiating wavelengths is included in the first ranges of filterwavelengths and excluded from the second ranges of filter wavelengths.The second set of differentiating wavelengths is included in the secondranges of filter wavelengths and excluded from the first ranges offilter wavelengths.

BRIEF DESCRIPTION OF THE DRAWINGS

The disclosed technique will be understood and appreciated more fullyfrom the following detailed description taken in conjunction with thedrawings in which:

FIG. 1 is a schematic illustration of a three-dimensional object and astereoscopic imaging apparatus, constructed and operative in accordancewith an embodiment of the disclosed technique;

FIG. 2 is a schematic illustration of a stereoscopic imaging apparatus,constructed and operative in accordance with another embodiment of thedisclosed technique;

FIG. 3A is a schematic illustration of a super-pixel, constructed andoperative in accordance with a further embodiment of the disclosedtechnique;

FIG. 3B is a schematic illustration of the super-pixel of FIG. 3A and alenticular element, constructed and operative in accordance with anotherembodiment of the disclosed technique;

FIG. 3C is a schematic illustration of a sensor array and a lenticularlens layer, constructed and operative in accordance with a furtherembodiment of the disclosed technique;

FIG. 4 is a schematic illustration of a super-pixel, constructed andoperative in accordance with another embodiment of the disclosedtechnique;

FIG. 5A is a schematic illustration of a color super-pixel, constructedand operative in accordance with a further embodiment of the disclosedtechnique;

FIG. 5B is a schematic illustration of the color super-pixel of FIG. 5A,with a single lenticular element, constructed and operative inaccordance with another embodiment of the disclosed technique;

FIG. 5C is a schematic illustration of the color super-pixel of FIG. 5A,combined with three lenticular elements, constructed and operative inaccordance with a further embodiment of the disclosed technique;

FIG. 6 is a schematic illustration of a sensor array and a lenticularlens layer, constructed and operative in accordance with anotherembodiment of the disclosed technique;

FIG. 7A is a schematic illustration of a method for operating theapparatus of FIG. 2, operative in accordance with a further embodimentof the disclosed technique;

FIG. 7B is an illustration in detail of a step of the method of FIG. 7A;

FIG. 7C is a schematic illustration of a sensor array and a lenticularlens layer, constructed and operative in accordance with anotherembodiment of the disclosed technique;

FIG. 8 is a schematic illustration of a stereoscopic imaging apparatus,constructed and operative in accordance with a further embodiment of thedisclosed technique;

FIG. 9A is a view in perspective of a section of light sensors, and alenticular element, constructed and operative in accordance with anotherembodiment of the disclosed technique;

FIG. 9B is a view from the bottom of the lenticular element and thesection of light sensors of FIG. 9A;

FIG. 9C is a view from the side of the lenticular element and thesection of light sensors of FIG. 9A;

FIG. 10 is a view in perspective of a section of light sensors, and alenticular element, constructed and operative in accordance with afurther embodiment of the disclosed technique;

FIG. 11 is a view in perspective of a sensor array and a lenticular lenslayer, constructed and operative in accordance with another embodimentof the disclosed technique;

FIG. 12A is a schematic illustration of a detection apparatus,constructed and operative in accordance with a further embodiment of thedisclosed technique;

FIG. 12B is another schematic illustration of the detection apparatus ofFIG. 12A;

FIG. 13 is a schematic illustration of a detection apparatus,constructed and operative in accordance with another embodiment of thedisclosed technique;

FIG. 14A is a partially schematic partially perspective illustration ofa combined illumination and detection device, constructed and operativein accordance with a further embodiment of the disclosed technique;

FIG. 14B is a partially schematic partially perspective illustration ofthe combined illumination and detection device of FIG. 14A, a controllerand output frames, constructed and operative in accordance with anotherembodiment of the disclosed technique;

FIG. 15 is an illustration in perspective of a color illumination unit,constructed and operative in accordance with a further embodiment of thedisclosed technique;

FIG. 16 is a view in perspective of a sensor array and a partiallenticular lens layer, constructed and operative in accordance withanother embodiment of the disclosed technique;

FIG. 17 is a view in perspective of a sensor array and a partiallenticular lens layer, constructed and operative in accordance with afurther embodiment of the disclosed technique;

FIG. 18 is a schematic illustration of a sensor array and a partiallenticular lens layer, constructed and operative in accordance withanother embodiment of the disclosed technique;

FIG. 19 is a schematic illustration of a sensor array and a partiallenticular lens layer, constructed and operative in accordance with afurther embodiment of the disclosed technique;

FIG. 20A is a schematic illustration of a system, for producing a colorstereoscopic image, in a right side detection mode, constructed andoperative in accordance with another embodiment of the disclosedtechnique;

FIG. 20B is an illustration of the system of FIG. 20A, in a left-sidedetection mode;

FIG. 21A is a schematic illustration of a timing sequence, in which thecontroller of the system of FIG. 20A synchronizes the operation ofillumination unit, apertures and image detector of that same system;

FIG. 21B is a schematic illustration of another timing sequence, inwhich the controller of FIG. 20A synchronizes the operation of theillumination unit, right and left apertures and the image detector;

FIG. 22 is a schematic illustration of a method for operating the systemof FIGS. 20A and 20B, operative in accordance with a further embodimentof the disclosed technique;

FIG. 23 is a schematic illustration of a timing scheme, for operatingthe system of FIGS. 20A and 20B, in accordance with another embodimentof the disclosed technique;

FIG. 24 is a schematic illustration of a timing scheme, for operatingthe system of FIGS. 20A and 20B, in accordance with a further embodimentof the disclosed technique;

FIG. 25A is a schematic illustration of an object and a sensor assembly,when the sensor assembly is located at an initial position with respectto the object;

FIG. 25B is a schematic illustration of the object and the sensorassembly of FIG. 25A, when the sensor assembly has moved to a newposition;

FIG. 25C is a schematic illustration of the object and the sensorassembly of FIG. 25A, when the sensor assembly has moved to anotherposition;

FIG. 25D is a schematic illustration of the object and the sensorassembly of FIG. 25A, when the sensor assembly has moved to a furthernew position;

FIG. 25E is a schematic illustration of the object and the sensorassembly of FIG. 25A, when the sensor assembly has moved to another newposition;

FIG. 25F is a schematic illustration of the object and the sensorassembly of FIG. 25A, when the sensor assembly has moved to a furthernew position;

FIG. 26A is a schematic illustration of a detected image, as detected bysensor assembly of FIG. 25A, and a respective displayed image, inaccordance with a further embodiment of the disclosed technique;

FIG. 26B is a schematic illustration of a detected image, as detected bysensor assembly of FIG. 25B, and a respective displayed image;

FIG. 26C is a schematic illustration of a detected image, as detected bythe sensor assembly of FIG. 25C, and a respective displayed image;

FIG. 27A is a schematic illustration of a sub-matrix, in accordance withanother embodiment of the disclosed technique, when the sensor assemblyis at a location illustrated in FIG. 25A;

FIG. 27B is a schematic illustration of a sub-matrix, when the sensorassembly is at a location illustrated in FIG. 25B;

FIG. 27C is a schematic illustration of a sub-matrix, when the sensorassembly is at a location illustrated in FIG. 25C;

FIG. 27D is a schematic illustration of a sub-matrix, when the sensorassembly is at a location illustrated in FIG. 25D;

FIG. 27E is a schematic illustration of a sub-matrix, when the sensorassembly is at a location illustrated in FIG. 25E;

FIG. 27F is a schematic illustration of a sub-matrix, when the sensorassembly is at a location illustrated in FIG. 25F;

FIG. 28A is a schematic illustration of a stereoscopic imagingapparatus, constructed and operative in accordance with a furtherembodiment of the disclosed technique;

FIG. 28B is a schematic illustration of the apparatus of FIG. 28A, inanother mode of imaging;

FIG. 29A is a schematic illustration of a stereoscopic imaging apparatusin a right side detection mode, constructed and operative in accordancewith another embodiment of the disclosed technique;

FIG. 29B is a schematic illustration of the apparatus of FIG. 29A, in aleft side detection mode;

FIG. 30A is a schematic illustration of a stereoscopic imaging apparatusin a right side filter mode, constructed and operative in accordancewith a further embodiment of the disclosed technique;

FIG. 30B is a schematic illustration of the apparatus of FIG. 30A, in aleft side filter mode;

FIG. 31A is a schematic illustration of a stereoscopic imaging apparatusin a right side view image mode, constructed and operative in accordancewith another embodiment of the disclosed technique;

FIG. 31B is a schematic illustration of the apparatus of FIG. 30A, in aleft side view image mode;

FIG. 32 is a schematic illustration of a method for operating astereoscopic imaging apparatus, operative in accordance with anotherembodiment of the disclosed technique;

FIG. 33A is a schematic illustration of an endoscope with a periscopeassembly thereof in a retracted mode, constructed and operative inaccordance with a further embodiment of the disclosed technique;

FIG. 33B is a schematic illustration of the periscope of the endoscopeof FIG. 33A, in an extended mode;

FIG. 34A is a schematic illustration of an endoscope with a periscopeassembly thereof in a retracted mode, constructed and operative inaccordance with another embodiment of the disclosed technique;

FIG. 34B is a schematic illustration of the periscope assembly of theendoscope of FIG. 34A, in an extended mode;

FIG. 35A is a schematic illustration of a stereoscopic imagingapparatus, constructed and operative in accordance with a furtherembodiment of the disclosed technique;

FIG. 35B is a schematic illustration of the apparatus of FIG. 35A, inwhich the periscope assembly thereof is in a different mode than that ofFIG. 35A;

FIG. 36 is a schematic illustration of a stereoscopic imaging apparatus,constructed and operative in accordance with another embodiment of thedisclosed technique;

FIG. 37A is a schematic illustration of a stereoscopic imagingapparatus, constructed and operative in accordance with a furtherembodiment of the disclosed technique;

FIG. 37B is a schematic illustration of a split fiber of the lightdirecting assembly of the apparatus of FIG. 37A;

FIG. 38A is a schematic illustration of a stereoscopic imagingapparatus, constructed and operative in accordance with anotherembodiment of the disclosed technique;

FIG. 38B is a schematic illustration of the apparatus of FIG. 38A, inanother mode of operation;

FIG. 39A is a schematic illustration of a partially-transparent rotatingdisk, constructed and operative in accordance with a further embodimentof the disclosed technique;

FIG. 39B is a schematic illustration of a partially-transparent rotatingdisk, constructed and operative in accordance with another embodiment ofthe disclosed technique;

FIG. 40A is a schematic illustration of a multi-wavelength rotatingdisk, constructed and operative in accordance with a further embodimentof the disclosed technique;

FIG. 40B is a schematic illustration of a multi-wavelength rotatingdisk, constructed and operative in accordance with another embodiment ofthe disclosed technique;

FIG. 41A is a schematic illustration of a top view of a stereoscopicimage scanning apparatus, constructed and operative in accordance with afurther embodiment of the disclosed technique;

FIG. 41B is a schematic illustration of side view (referenced A in FIG.41A) of the apparatus of FIG. 41A, in one mode of scanning;

FIG. 41C is a schematic illustration of the apparatus of FIG. 41B, inanother mode of scanning;

FIG. 42A is a schematic illustration of a stereoscopic imagingapparatus, constructed and operative in accordance with anotherembodiment of the disclosed technique;

FIG. 42B is a schematic illustration of the stereoscopic imagingapparatus of FIG. 42A, in another mode of operation;

FIG. 43 is a schematic illustration of a method for operating astereoscopic imaging apparatus, operative in accordance with a furtherembodiment of the disclosed technique;

FIG. 44A is a schematic illustration of a rotating disk, constructed andoperative in accordance with another embodiment of the disclosedtechnique;

FIG. 44B is a schematic illustration of a rotating disk, constructed andoperative in accordance with a further embodiment of the disclosedtechnique;

FIG. 45A is a schematic illustration of a stereoscopic imagingapparatus, constructed and operative in accordance with anotherembodiment of the disclosed technique;

FIG. 45B is a schematic illustration of a top view of the apparatus ofFIG. 45A;

FIG. 46A is a schematic illustration of a physical object and astereoscopic imaging apparatus, constructed and operative in accordancewith a further embodiment of the disclosed technique;

FIG. 46B is a schematic illustration of the apparatus of FIG. 46A, witha different set of light rays shown; and

FIG. 47 is a schematic illustration of an aperture stop, constructed andoperative in accordance with another embodiment of the disclosedtechnique.

DETAILED DESCRIPTION OF THE EMBODIMENTS

The disclosed technique overcomes the disadvantages of the prior art byproviding a continuous imaging stereoscopic apparatus, using a generallylenticular lens layer, a light sensor array and an image processingsystem.

Reference is now made to FIG. 1, which is a schematic illustration of athree-dimensional object 150 and a stereoscopic imaging apparatus,generally referenced 100, constructed and operative in accordance withan embodiment of the disclosed technique. Apparatus 100 includes alenticular lens layer 104, a light sensor array 102, a processor 106 andtwo display devices 108R and 108L. Apparatus 100 is placed in front ofthree-dimensional object 150. An optical assembly 152 is placed betweenapparatus 100 and object 150, for focusing the image of object 150 onlight sensor array 102.

Light sensor array 102 includes a plurality of sensors 110, 111, 112,113, 114, 115, 116, 117, 118 and 119. Lenticular lens layer 104 includesa plurality of lenticular elements 130, 132, 134, 136 and 138. Each oneof the lenticular elements is located above two light sensors, in a waythat lenticular element 130 is located above sensors 110 and 111,lenticular element 132 is located above sensors 112 and 113, lenticularelement 134 is located above sensors 114 and 115, lenticular element 136is located above sensors 116 and 117 and lenticular element 138 islocated above sensors 118 and 119.

The light sensors 110, 111, 112, 113, 114, 115, 116, 117, 118, and 119,detect light as directed by the lenticular lens elements 130, 132, 134,136 and 138, and provide respective information to the processor 106.The processor 106 processes this information, produces a pair of images,as will be explained in detail herein below, and provides them to thedisplay units 108R and 108L, which in turn produce visualrepresentations of these images.

In general, each lenticular element directs light rays, which arrivefrom a predetermined direction to a predetermined location, and lightrays which arrive from another predetermined direction, to anotherpredetermined location. Hence, the disclosed technique, utilizes thelenticular lens layer to distinguish between a right view image and aleft view image, as is described herein below.

Each of the display units 108R and 108L includes a plurality of displayunits also known as pixels. Display unit 108L includes pixels 142A,142B, 142C, 142D and 142E. Display unit 108R includes pixels 144A, 144B,144C, 144D and 144E. Using these pixels each of the display units 108Rand 108L produces an image, according to data provided from theprocessor 106. The two images, each viewed by a different eye of theuser, produce a sensation of a three-dimensional image.

Light rays 124A, and 126A represent a right-side image of thethree-dimensional object 150. Light rays 120A, and 122A represent a leftside image of the three-dimensional object 150. The optical assembly 152redirects light rays 120A, 122A, 124A and 126A so as to focus them on aplain which is determined by the light sensor array 102, as light rays120B, 122B, 124B and 126B, respectively. Hence, light rays 122B and 126Brepresent a focused right side view of the three-dimensional object 150,and light rays 120B and 124B represent a focused left side view of thethree-dimensional object 150.

The lenticular lens layer 104 directs the focused right side view lightrays 122B and 126B to light sensors 110 and 118, respectively, asrespective light rays 122C and 126C. In addition, the lenticular lenslayer 104 directs the focused left side view light rays 120B and 124B tolight sensors 111 and 119, respectively. In general, light sensors 111,113, 115, 117 and 119 detect light rays which relate to a left side viewimage of object 150, and light sensors 110, 112, 114, 116, and 118,detect light rays which relate to a right side view image of object 150.

Hence, light sensors 110, 112, 114, 116 and 118 detect the right sideimage of object 150, while light sensors 111, 113, 115, 117 and 119detect the left side image of object 150. The light sensor array 102provides data relating to the detected light intensity at each of thelight sensors to the processor 106. It is noted that in the followingdescription, the term processor, refers to a control unit which isadapted for a given situation such as a CPU, a controller, a processor,a gated element, a timing unit such as a clock, and the like.Accordingly, the terms CPU, controller, processor, gated element, timingunit, clock, and the like, are interchangeable, with respect to a givenarchitecture or a given method.

The processor 106 processes this data, produces a right side image fromthe data relating to the right side view and a left side image from thedata relating to the left side view, and provides the respective imageto the respective display unit 108R and 108L. In the present example,the processor 106 utilizes the data received from sensors 110, 112, 114,116 and 118 to determine the data provided to pixels 144A, 144B, 144C,144D and 144E, respectively. Similarly, the processor 106 utilizes thedata received from sensors 111, 113, 115, 117 and 119 to determine thedata which is to be provided to pixels 142A, 142B, 142C, 142D and 142E,respectively.

According to the disclosed technique, the right side image and the leftside image are detected at the same time and hence, can also bedisplayed at the same time. According to another aspect of the disclosedtechnique, each of the light sensors 110, 111, 112, 113, 114, 115, 116,117, 118, and 119, includes a plurality of color sensing elements, whichtogether cover a predetermined spectrum, as will be described in detailherein below.

Reference is now made to FIG. 2, which is a schematic illustration of astereoscopic imaging apparatus, generally referenced 200, constructedand operative in accordance with another embodiment of the disclosedtechnique. Apparatus 200 includes a sensor assembly 202, an interface210, a processor 208, a movement detector 230, a light source 206, amemory unit 204, a stereoscopic video generator 212 and a stereoscopicdisplay 214. The sensor assembly 202 is coupled with the interface 210by a flexible cord 218. The interface 210 is coupled with processor 208,memory unit 204, and with light source 206. The processor 208 is furthercoupled with the memory unit 204, movement detector 230 and with thestereoscopic video generator 212. The stereoscopic video generator 212is further coupled with the stereoscopic display 214. Movement detector230 detects the movement of sensor assembly 202 relative to an object.For this purpose, movement detector 230 is attached to sensor assembly202. In the case of a rigid endoscope, the movement detector 230 can beattached to any part of the endoscope rod (not shown), since themovement of the endoscope head can be determined according to themovement of any point of the endoscope rod. The operation of system 200,according to data received from movement detector 230, is describedherein below.

The sensor assembly 202 includes a focusing element, which in thepresent example is a lens 226, a lenticular lens layer 222, a lightsensor array 220, an interface 228 and a light projecting means 224. Thelenticular lens layer 222 is attached to the light sensor array 220.According to the disclosed technique, the light sensor array 220 can beany type of sensing array, such as a CCD detector, a CMOS detector, andthe like. The light sensor array 220 is coupled with the interface 228,which can also acts as a supporting base.

The stereoscopic display 214 includes two display units, a left displayunit 216L (for placing in front of the left eye of the user) and a rightdisplay unit 216R (for placing in front of the right eye of the user).Hence, the stereoscopic display 214 is capable of displayingstereoscopic images continuously. Such a stereoscopic display unit isfor example the ProView 50 ST head-mounted display, manufactured andsold by Kaiser Electro-Optics Inc., a US registered company, located inCarlsbad, Calif. Another example for a stereoscopic display unit is thevirtual retinal display (VRD) unit, which is provided by MICROVISIONInc., a US registered company, located in Seattle, Wash. It is notedthat any method, which is known in the art for displaying stereoscopic,and for that matter three-dimensional images, is applicable for thedisclosed technique.

The image received from a three-dimensional object is received at thesensor assembly 202, focused by lens 226, optically processed by thelenticular lens layer 222 and finally detected by the light sensor array220. The lenticular lens layer 222 directs light coming from onepredetermined direction to predetermined light sensors of the lightsensor array 220, and light coming from another predetermined directionto other predetermined light sensors of the light sensor array 220.Accordingly, light sensor array 220 detects two images of the sameobject, a right side image and a left side image, each from a differentdirection. This aspect of the disclosed technique is described in detailhereinabove, in conjunction with FIG. 1.

An electronic representation of this information is partially processedby the interface 228 and then provided to the interface 210, viaflexible cord 218. It is noted that flexible cord 218 may includedigital communication linking means such as optic fibers or electricalwires, for transferring data received from light sensor array 220, aswell as light guiding conducting means for conducting light from lightsource 206 to the light projecting means 224. According to the disclosedtechnique, flexible cord 218 can be replaced with a rigid cord (notshown), if necessary.

The data received at interface 210 includes information, which relatesto the two images and has to be processed so as to distinguish them fromeach other. As the processor 208 processes the information, it uses thememory unit 204 as temporarily storage.

After processing the information, the processor 208 produces twomatrices each being a reconstructed representation relating to one ofthe originally detected images. The processor provides these matrixes tothe stereoscopic video generator 212, which in turn produces tworespective video signals, one for the left view image and another forthe right view image.

The stereoscopic video generator 212 provides the video signals to thestereoscopic display 214, which in turn produces two images, one usingright display unit 216R and another using left display unit 216L.

It is noted that the general size of the sensor assembly 202 is dictatedby the size of the sensor array and can be in the order of a fewmillimeters or a few centimeters. This depends on the size of each ofthe sensors in the array and the total number of sensors (i.e. therequired optical resolution).

According to one aspect of the disclosed technique, each of the sensorsin light sensor array 220, is a full range sensor, which yields datarelating to a gray scale stereoscopic image. According to another aspectof the disclosed technique, each of the sensors in the light sensorarray, can be adapted so as to provide full color detectioncapabilities.

Reference is now made to FIG. 3A, which is a schematic illustration of asuper-pixel, generally referenced 300, constructed and operative inaccordance with a further embodiment of the disclosed technique.Super-pixel 300 includes a left section of sensors which includes threesensors 302, 304 and 306, and a right section of sensors which alsoincludes three sensors 308, 310 and 312. Sensors 302 and 310 detectgenerally red colored light, sensors 304 and 312 detect generally greencolored light and sensors 306 and 308 detect generally blue coloredlight. Hence, each of the sections includes a complete set of sensorsfor detecting light in the entire visible spectrum.

Reference is further made to FIG. 3B, which is a schematic illustrationof the super-pixel 300 of FIG. 3A and a lenticular element, generallyreferenced 318, constructed and operative in accordance with anotherembodiment of the disclosed technique. The lenticular element 318 islocated on top of super-pixel 300, such that its right side covers theright section of the super-pixel 300, and its left side covers the leftsection of the super-pixel 300. Accordingly, the lenticular element 318directs light, which arrives from the right (right view image), to theleft section of the super-pixel 300, where it is detected in fullspectrum by sensors 302, 304 and 306.

The data provided by these sensors can later be utilized to reconstructan image in full color. Similarly, the lenticular element 318 directslight, which arrives from the left (left view image), to the rightsection of the super-pixel 300, where it is detected in full spectrum bysensors 308, 310 and 312.

Reference is now made to FIG. 3C, which is a schematic illustration of asensor array, generally referenced 330, and a lenticular lens layer,generally referenced 332, constructed and operative in accordance with afurther embodiment of the disclosed technique. Sensor array 330 is amatrix of M×N super-pixels, which are generally referenced 340. Forexample, the upper left super-pixel is denoted 340 _((1,1)), the lastsuper-pixel in the same column is denoted 340 _((1,N)) and thelower-right pixel is denoted 340 _((M,N)). Lenticular lens layer 332, ofwhich three lenticular elements are shown (referenced 334), is placedover the sensor array 330.

Lenticular element 334 ₍₁₎ covers the first column of super-pixels 340from super-pixel 340 _((1,1)) to super-pixel 340 _((1,N)). Lenticularelement 334 ₍₂₎ covers the second column of super-pixels 340 fromsuper-pixel 340 _((2,1)) to super-pixel 340 _((2,N)). Lenticular element334 ₍₃₎ covers the third column of super-pixels 340 from super-pixel 340_((3,1)) to super-pixel 340 _((3,N)). Accordingly, each of thelenticular elements of the lenticular lens layer covers an entire columnof super-pixels.

It is noted that a super-pixel according to the disclosed technique caninclude sensors in any set of colors such as red-green-blue (RGB),cyan-yellow-magenta-green (CYMG), infra-red, ultra-violet, and the like,in any arrangement or scheme such as column, diagonals, and the like. Itis noted that such a set of colors can be achieved either by usingspecific color sensitive detectors or by using color filters over thewide spectrum detectors.

The output of a conventional CYMG sensor array can include a pluralityof values, each of which is equal to the sum of two cells in the samecolumn and in adjacent rows. The following sums may apply in aconventional CYMG sensor array—Cyan+Magenta, Yellow+Green, Cyan+Greenand Yellow+Magenta.

Reference is further made to FIG. 4, which is a schematic illustrationof a super-pixel, generally referenced 350, constructed and operative inaccordance with another embodiment of the disclosed technique.Super-pixel 350 includes a left section of sensors which includes foursensors 352, 354, 356 and 358 and a right section of sensors which alsoincludes four sensors 360, 362, 364 and 366. Sensors 352 and 366 detectgenerally cyan colored light, sensors 354 and 360 detect generallyyellow colored light, sensors 356 and 362 detect generally magentacolored light and sensors 358 and 364 detect generally green coloredlight. Hence, each of the sections includes a complete set of sensorsfor detecting light in the entire visible spectrum.

Reference is further made to FIGS. 5A, 5B and 5C. FIG. 5A is a schematicillustration of a super-pixel, generally referenced 370, constructed andoperative in accordance with a further embodiment of the disclosedtechnique. FIG. 5B is a schematic illustration of super-pixel 370combined with a single lenticular element, generally referenced 384,constructed and operative in accordance with another embodiment of thedisclosed technique. FIG. 5C is a schematic illustration of super-pixel370 combined with three lenticular elements, generally referenced 386,constructed and operative in accordance with a further embodiment of thedisclosed technique.

The color arrangement which is provided for super-pixel 370 is typicalfor vertical light detection arrays, where each column of sensors iscoated with light filtering layer of a different color. As can be seenin FIG. 5A, super-pixel 370 includes a plurality of light sensors 372,374, 376, 378, 380 and 382. Light sensors 372 and 378 are blue colorrange sensors. Light sensors 374 and 380 are green color range sensors.Light sensors 376 and 382 are red color range sensors.

Reference is now made to FIG. 6, which is a schematic illustration of asensor, generally referenced 390, and a lenticular lens layer, generallyreferenced 392, constructed and operative in accordance with anotherembodiment of the disclosed technique. Sensor 390 is logically dividedinto a plurality of super-pixels, generally referenced 394 _((x,y)). Forexample, the upper-left super-pixel is referenced 394 _((1,1)) and thelower-right side super-pixel is referenced 394 _((M,N)). As can be seenfrom FIG. 6, the color arrangement of sensor 390 is diagonal. Hence,each super pixel has a different color arrangement, and generallyspeaking, there are several types of super-pixels, such as red-blue(super pixel 394 _((M-2,N))), green-red (super pixel 394 _((M-1,N))) andblue-green (super pixel 394 _((M,N))).

Reference is now made to FIG. 7A, which is a schematic illustration of amethod for operating apparatus 200, operative in accordance with afurther embodiment of the disclosed technique. In step 400, theapparatus 200 splits light which arrives from different directions,utilizing the lenticular lens 222. Each of the lenticular elementsproduces two light sectors, one sector which includes light raysarriving from the left side, and another sector which includes lightrays arriving from the right side.

In step 402, the apparatus detects each light sector separately, using aplurality of light detectors, each detecting a portion of its respectivesector. With reference to FIG. 3B, sensors 302, 304 and 306 detect lightwhich arrives from the lenticular element 318, at the left side sectorand sensors 308, 310 and 312 detect light which arrives from thelenticular element 318, at the right side sector. Each of the sensorsdetects light at a sub-sector.

In step 404, the apparatus 200 determines the light characteristics asdetected by each of the light sensors, at each of the sub-sectors. Instep 408, the apparatus 200 utilizes the data, which was accumulatedfrom selected sub-sectors to determine and produce an image representinga view from one side. In step 406, the apparatus 200 utilizes the data,which was accumulated from other selected sub-sectors to determine andproduce an image representing a view from another side. In step 410, theapparatus 200 displays both images using a continuous stereoscopicdisplay device.

According to a further aspect of the disclosed technique, informationfrom selected pixels can be used to enhance information for otherpixels. For example, color information of pixels, which are associatedwith a first color, is used for extrapolating that color at the locationof another pixel, associated with a second color.

Reference is further made to FIGS. 7B and 7C. FIG. 7B is an illustrationin detail of step 406 of FIG. 7A. FIG. 7C is a schematic illustration ofa sensor array, generally referenced 450, and a lenticular lens layer,generally referenced 452, constructed and operative in accordance withanother embodiment of the disclosed technique. Sensor array 450 includesa plurality of pixel sensors, referenced 454, each associated with aselected color. For example, pixel sensors R_((1,1)), R_((2,2)),R_((3,3)), R_((4,4)), R_((1,4)) and R_((4,1)) are associated with thered color. Pixel sensors G_((2,1)), G_((3,2)), G_((4,3)), G_((1,3)) andG_((2,4)) are associated with the green color. Pixel sensors B_((1,2)),B_((2,3)), B_((3,4)), B_((3,1)) and B_((4,2)) are associated with theblue color.

In step 420, the system, according to the disclosed technique, selects apixel sensor, associated with a first color. With reference to FIG. 7C,the selected pixel sensor according to the present example is pixelsensor R_((3,3)).

In step 422, the system determines pixels, associated with a secondcolor, in the vicinity of the selected pixel. It is noted that thesepixels can also be restricted to ones, which relate to the same imageside of the selected pixel. With reference to FIG. 7C, the second coloris green and the green pixel sensors, in the vicinity of pixel sensorR_((3,3)), respective of the same image side are pixel sensorsG_((5,1)), G_((3,2)), G_((3,5)), G_((5,4)), and G_((1,3)).

In step 424, the system calculates an approximation of the level of thegreen color at the location of the selected pixel R_((3,3)). It is notedthat the calculation can include a plurality of approximationprocedures, such as calculating the weighted average level, depending onthe location of pixel sensors G_((5,1)), G_((3,2)), G_((3,5)),G_((5,4)), and G_((1,3)), with respect to the location of the selectedpixel sensor R_((3,3)). Similarly, blue color level at the location ofthe selected pixel sensor R_((3,3)), can be calculated using theinformation received from pixel sensors B_((1,2)), B_((1,5)), B_((3,1)),B_((3,4)) and B_((5,3)). Hence the disclosed technique provides a methodfor enhancing picture resolution by means of color informationinterpolation, using image processing.

It is noted that none of the lenticular elements is necessarily roundshaped, but can be formed according to other optical structures whichare based on various prism designs, and the like, which provide thedirecting of beams of light coming from different directions todifferent directions.

Reference is now made to FIG. 8, which is a schematic illustration of astereoscopic imaging apparatus, generally referenced 500, constructedand operative in accordance with a further embodiment of the disclosedtechnique. Apparatus 500 includes a sensor assembly 502, a frame grabber510, a processor 508, a light source 506, a memory unit 504, astereoscopic video generator 512 and a stereoscopic display 514. Thesensor assembly 502 is coupled with the frame grabber 510 by a flexiblecord 518. The frame grabber 510, the processor 508, the memory unit 504and the stereoscopic video generator 512 are all interconnected via acommon bus.

The sensor assembly 502 is generally similar to the sensor assembly 202,as described herein above in conjunction with FIG. 2. The sensorassembly 502 includes a lens 526, a lenticular lens layer 522, a lightsensor array 520, an analog to diconverter (A/D) 528 and a lightprojecting means 524. The lenticular lens layer 522 is attached to thelight sensor array 520. Light sensor array 520 is coupled with the A/D528, which could also act as a supporting base. The light projectingmeans 524 is coupled with light source 506, which provides lightthereto.

The stereoscopic display 514 includes two display units, a left displayunit 516L (for placing in front of the left eye of the user), and aright display unit 516R (for placing in front of the right eye of theuser). Hence, the stereoscopic display 514 is capable of displayingstereoscopic images continuously. A/D converter 528 converts analoginformation received from light sensor array 522 into digital format andprovides the digital information to frame grabber 510.

The digital information is received by the frame grabber 510 and hencemade available to the processor 508 via the bus. As the processor 508processes the information, it uses the memory unit 504 as temporarystorage. After processing the information, the processor 508 producestwo matrices each being a reconstructed representation relating to oneof the originally detected images. The processor 508 provides thesematrices to the stereoscopic video generator 512, which in turn producestwo respective video signals, one for the left view image and anotherfor the right view image. The stereoscopic video generator 512 providesthe video signals to the stereoscopic display 514, which in turnproduces two images, one using right display unit 516R and another usingleft display unit 516L.

Reference is now made to FIGS. 9A, 9B and 9C. FIG. 9A is a view inperspective of a super-pixel, generally referenced 550, and a lenticularelement, generally referenced 552, constructed and operative inaccordance with another embodiment of the disclosed technique. FIG. 9Bis a view from the bottom of the lenticular element 552 and thesuper-pixel 550 of FIG. 9A. FIG. 9C is a view from the side of thelenticular element 552 and the super-pixel 550 of FIG. 9A.

The super-pixel 550 includes four sensor sections, 554, 556, 558 and560, arranged in a rectangular formation. The lenticular element 552 isshaped like a dome and is basically divided into four sections, eachfacing a different one of the sensor sections 554, 556, 558 and 560.

The super-pixel 550 and the lenticular element 552 form together, anoptical detection unit, which is capable of detecting and distinguishinglight which arrives from four different directions. The lenticularelement 552 directs a portion of the upper-left side view of thedetected object to sensor section 554 and directs a portion of thelower-left side view of the detected object to sensor section 556. Inaddition, the lenticular element 552 directs a portion of theupper-right side view of the detected object to sensor section 560 and aportion of the lower-right side view of the detected object to sensorsection 558.

It is noted that according to a further aspect of the disclosedtechnique, the four-direction arrangement, which is described in FIGS.9A, 9B and 9C can be used to logically rotate the image which isprovided to the user, without physically rotating the device itself. Atfirst, sensor sections 560 and 558 are used to form the right-side imageand sensor sections 554 and 556 are used to form the left-side image. Arotation at an angle of 90° clockwise, is provided by assigning sensorsections 554 and 560, to form the right side image, and assigning sensorsections 556 and 558, to form the left-side image. It is further notedthat a rotation in any desired angle can also be performed by means of alinear or other combination of sensor sections, when reconstructing thefinal images.

Reference is now made to FIG. 10, which is a view in perspective of asection of light sensors, generally referenced 570, and a lenticularelement, generally referenced 572, constructed and operative inaccordance with a further embodiment of the disclosed technique.Lenticular element 572 is extended to cover the entire area of thesection of pixels, so as to enhance light transmission thereto.

Reference is now made to FIG. 11, which is a view in perspective of asensor array, generally referenced 580, and a lenticular lens layer,generally referenced 582, constructed and operative in accordance withanother embodiment of the disclosed technique. The lenticular lens layer582 includes a plurality of four direction lenticular elements such asdescribed in FIGS. 9A and 10. The sensor array 580 is logically dividedinto a plurality of sensor sections, generally referenced 584 _((x,y)).For example, the upper left sensor section is referenced 584 _((1,1))and the lower-right sensor section is referenced 584 _((M,N)). Each ofthe sensor sections is located beneath a lenticular element and detectslight directed thereby.

Reference is now made to FIGS. 12A and 12B. FIG. 12A is a schematicillustration of a detection apparatus, generally referenced 600,constructed and operative in accordance with a further embodiment of thedisclosed technique. FIG. 12B is another schematic illustration ofdetection apparatus 600, of FIG. 12A.

Detection apparatus 600 includes an optical assembly 602, a lenticularlens layer 604 and an array of sensors 608. The detection apparatus 600detects images of an object 610, which includes a plurality of objectsections 610A, 610B, 610C and 610D.

Sensor array 608 includes a plurality of super-pixels 608A, 608B, 608Cand 608D. Each of these super-pixels is divided into a left-side sectionand a right-side section. For example, super-pixel 608A includes aleft-side section, designated 608A_(L) and a right-side section,designated 608A_(R).

The optical assembly 602 is divided into two optical sections 602 _(L)and 602 _(R), each directed at transferring an image, which represents adifferent side view. Optical section 602 _(R) transfers an image, whichis a view from the right side of object 610. Optical section 602 _(L)transfers an image, which is a view from the left side of object 610.

A plurality of light rays 612, 614, 616 and 618 are directed from allsections of the object 610 to the left side of optical assembly 602(i.e., optical section 602 _(L)), and from there, are directed to thelenticular lens layer 604. Here, these rays are further directed to theleft-side view associated sensor sections, which are sensor sections 608_(L) (i.e., sensor sections 608A_(L), 608B_(L), 608C_(L) and 608D_(L)).

With reference to FIG. 12B, a plurality of light rays 622, 624, 626 and628 are directed from all sections of the object 610 to the right sideof optical assembly 602 (i.e., optical section 602 _(R)), and fromthere, are directed to the lenticular lens layer 604. Here, these raysare further directed to the right-side view associated sensor sections,which are sensor sections 608A_(R), 608B_(R), 608C_(R) and 608D_(R).

Reference is now made to FIG. 13, which is a schematic illustration of adetection apparatus, generally referenced 630, constructed and operativein accordance with another embodiment of the disclosed technique.Detection apparatus 630 includes an optical assembly, which is dividedinto four sections 632, 634, 636 and 638, a lenticular lens layer 642and an array of sensors 640. The detection apparatus 630 detects imagesof an object 648, which includes a plurality of object sections 648A,648B, 648C, 648D, 648E and 648F. Light rays, which arrive from object648 to any of the optical sections, are directed to a lenticular elementof the lenticular lens layer 642, according to their origin.

In the present example, all of the light rays 646A, 646B, 646C and 646Darrive from object element 648A. Each of these rays is received at adifferent optical section. Ray 646A is received and directed by opticalsection 636, ray 646B is received and directed by optical section 638,ray 646C is received and directed by optical section 634 and ray 646D isreceived and directed by optical section 632. Each of the opticalsections directs its respective ray to a specific lenticular element 642_((1,1)), at the right side of the lenticular lens layer 642. Thelocation of lenticular element 642 _((1,1)) is respective of thelocation of the object element 648A. The lenticular element 642 _((1,1))directs each of the rays to predetermined light sensors within itsrespective super-pixel 640 _((1,1)).

In accordance with a further aspect of the disclosed technique, there isprovided a reduced size color stereovision detection system, which usestime-multiplexed colored light projections, and respectivetime-multiplexed frame grabbing.

Reference is now made to FIGS. 14A and 14B. FIG. 14A is a partiallyschematic, partially perspective illustration of a combined illuminationand detection device, generally referenced 650, constructed andoperative in accordance with a further embodiment of the disclosedtechnique. FIG. 14B is a partially schematic, partially perspectiveillustration of the combined illumination and detection device 650 ofFIG. 14A, a controller, generally designated 662, and output frames,constructed and operative in accordance with another embodiment of thedisclosed technique.

Device 650 includes a lenticular lens layer 652, a full spectrum sensorarray 654, an optical assembly 660 and an illuminating unit 656,surrounding the optical assembly 660. Illuminating unit 656 includes aplurality of illuminating elements, generally referenced 658, each beingof a specific predetermined color. Illuminating elements 658 _(RED)produce generally red light, illuminating elements 658 _(GREEN) producegenerally green light and illuminating elements 658 _(BLUE) producegenerally blue light. It is noted that each of the illuminating elementscan be of a specific color (i.e., a specific wavelength), a range ofcolors (i.e., a range of wavelengths) or alternating colors, forexample, a multi-color light emitting diode (LED).

Each group of illuminating elements, which are of the same color, isactivated at a different point in time. For example, illuminatingelements 658 _(RED) are activated and shut down first, illuminatingelements 658 _(GREEN) are activated and shut down second andilluminating elements 658 _(BLUE) are activated and shut down last. Thenthe illuminating sequence is repeated.

With reference to FIG. 14B, the controller 662 is coupled with thesensor array 654 and to the illuminating unit 656. The sensor array 654includes full spectrum sensors, which are capable of detecting red,green and blue light, but cannot indicate the wavelength of the detectedlight. The controller 662 associates the images, which are detected atany particular moment, using the sensor array 654, with the color of theilluminating elements, which were active at that particular moment.

Hence, the first detected frame 664 in an illumination sequence isconsidered red, since the illuminating elements which were active atthat time, were illuminating elements 658 _(RED). Similarly, the seconddetected frame 666 in an illumination sequence is considered green,since the illuminating elements, which were active at that time, wereilluminating elements 658 _(GREEN). Finally, the last detected frame 668in an illumination sequence is considered blue, since the illuminatingelements, which were active at that time, were illuminating elements 658_(BLUE). It is noted that any other combination of colors is applicablefor this and any other aspect of the disclosed technique, such as CYMG,and the like.

Reference is now made to FIG. 15, which is an illustration inperspective of a color illumination unit, generally referenced 670,constructed and operative in accordance with a further embodiment of thedisclosed technique. Unit 670 includes a light-guiding element 671,which is generally shaped as an open-cut hollow cone, having a narrowsection 674 and a wide section 672. A detection head according to thedisclosed technique, such as described in FIG. 2 (referenced 202), canbe placed within the hollow space of the light-guiding element 671. Amulti-color light source 680 can be coupled with the narrow section 674.Light, such as light ray 678, which is emitted from the light source680, is directed via the light guiding element 671, and is projectedthrough the wide section 672.

According to a further aspect of the disclosed technique, a remotemulti-color light source 682 can be coupled with the narrow section 674via additional light guiding members such as optic-fibers 684. Light,such as light ray 676, which is emitted from the light source 682, isdirected via the light guiding members 684 to the narrow section 674.The light-guiding element 671 guides light ray 676, and projects itthrough the wide section 672. This arrangement is useful when using anexternal light source, which is to be placed outside the inspected area(for example, outside the body of the patient).

According to a further aspect of the disclosed technique, a fullspectrum illumination unit, which produces white light, is combined witha device such as sensor assembly 202 (FIG. 2).

Reference is now made to FIG. 16, which is a view in perspective of asensor array, generally referenced 700, and a partial lenticular lenslayer, generally referenced 702, constructed and operative in accordancewith another embodiment of the disclosed technique. The partiallenticular lens layer 700 includes a plurality of four directionlenticular elements 702 such as described in FIGS. 9A and 10. The sensorarray 700 is logically divided into a plurality of sensor sections,generally referenced 704 _((x,y)). For example, the upper left sensorsection is referenced 704 _((1,1)) and the lower-right sensor section isreferenced 704 _((M,N)). Some of the sensor sections, in the perimeter,are located beneath lenticular elements and others, such as the sensorsections in the center rectangle, which is defined by sensor sections704 _((4,3))-704 _((7,6)) are not. Accordingly, the sensors which arelocated at the center rectangle can not be used to providemulti-direction (stereoscopic or quadroscopic) information. Instead,these sensors provide enhanced resolution monoscopic information.

Reference is now made to FIG. 17, which is a view in perspective of asensor array, generally referenced 720, and a partial lenticular lenslayer, generally referenced 722, constructed and operative in accordancewith a further embodiment of the disclosed technique. The partiallenticular lens layer 720 includes a plurality of four directionlenticular elements such as described in FIGS. 9A and 10. The sensorarray 720 is logically divided into a plurality of sensor sections,generally referenced 724 _((x,y)). For example, the upper left sensorsection is referenced 724 _((1,1)) and the lower-right sensor section isreferenced 724(M,N). Here, some of the sensor sections, in the center,(such as sensor section 724 _((4,2))) are located beneath lenticularelements and others, such as the sensor sections in the perimeter (suchas sensor section 724 _((1,1))) are not. Accordingly, the sensors whichare located at the center provide multi-direction (stereoscopic orquadroscopic) information and the ones in the perimeter provide enhancedresolution monoscopic information.

In accordance with a further aspect of the disclosed technique there isprovided a partial lenticular lens layer, which includes spaced apartlenticular elements. Reference is now made to FIG. 18, which is aschematic illustration of a sensor array, generally referenced 740, anda partial lenticular lens layer, generally referenced 742, constructedand operative in accordance with another embodiment of the disclosedtechnique.

The partial lenticular lens layer 742 includes a plurality of lenticularelements designated 744 ₍₁₎, 744 ₍₂₎ and 744 ₍₃₎. Lenticular element 744₍₁₎ is located over the first two left columns of color sensors,generally referenced 746 ₍₁₎, of sensor array 740. Hence, theinformation received from these first two left columns of color sensorsof sensor array 740 contains stereoscopic information. The third andfourth columns of color sensors, generally designated 746 ₍₂₎, of sensorarray 740 do not have a lenticular element located thereon, and hence,cannot be used to provide stereoscopic information.

Similarly, lenticular element 744 ₍₂₎ and 744 ₍₃₎ are located over colorsensor column pairs, 746 ₍₃₎ and 746 ₍₅₎, respectively, while colorsensor column pairs, 746 ₍₄₎ and 746 ₍₆₎ are not covered with lenticularelements.

Reference is now made to FIG. 19, which is a schematic illustration of asensor array, generally referenced 760, and a partial lenticular lenslayer, generally referenced 762, constructed and operative in accordancewith another embodiment of the disclosed technique. Lenticular lenslayer 762 includes a plurality of lenticular elements, referenced 764₍₁₎, 764 ₍₂₎, 764 ₍₃₎ and 764 ₍₄₎, being of different sizes and locatedat random locations over the sensor array 760. It is noted that anystructure of partial lenticular lens layer is applicable for thedisclosed technique, whereas the associated image processing applicationhas to be configured according to the coverage of that specificlenticular lens layer, and to address covered sensors and uncoveredsensors appropriately.

In accordance with a further aspect of the disclosed technique, there isprovided a system, which produces a color stereoscopic image. Thestructure of the stereoscopic device defines at least two viewingangles, through which the detector can detect an image of an object.According to one aspect of the disclosed technique, the stereoscopicdevice includes an aperture for each viewing angle. Each of theapertures can be opened or shut. The stereoscopic device captures astereoscopic image, by alternately detecting an image of an object, fromeach of the viewing angles, (e.g., by opening a different aperture at atime and shutting the rest) through a plurality of apertures, (at leasttwo), each time from a different aperture. The final stereoscopic imagecan be reconstructed from the images captured with respect to thedifferent viewing angles.

The detection of stereoscopic color image is provided by illuminatingthe object with a sequence of light beams, each at a differentwavelength, and detecting a separate image for each wavelength andaperture combination.

Reference is now made to FIGS. 20A and 20B. FIG. 20A is a schematicillustration of a system, generally referenced 800, for producing acolor stereoscopic image, in a right side detection mode, constructedand operative in accordance with a further embodiment of the disclosedtechnique. FIG. 20B is an illustration of the system of FIG. 20A, in aleft-side detection mode.

System 800 includes a multiple aperture 804, a controller 834, an imagedetector 812, a storage unit 836, an image processor 838, a movementdetector 814 and an illumination unit 830. The controller 834 is coupledwith the multiple aperture 804, the image detector 812, the storage unit836, movement detector 814 and to the illumination unit 830. The storageunit 836 is further coupled with the image processor 838. The multipleaperture 804 includes a plurality of apertures, generally referenced 802_(i), where each aperture can be activated to be open or closed. It isnoted that when an aperture is open it is at least transparent to apredetermined degree to light, and when an aperture is closed, itsubstantially prevents the travel of light there through. Any type ofcontrollable light valve can be used to construct each of the apertures.Movement detector 814 detects the movement of image detector 812. Thedetected movement can be a linear displacement, an angular displacement,and the derivatives thereof such as velocity, acceleration, and thelike. The operation of system 800, according to data received frommovement detector 814, is described herein below in connection withFIGS. 25A, 25B, 25C, 26A, 26B and 26C.

Light valve elements are components, which have an ability to influencelight in at least one way. Some of these ways are, for example:scattering, converging, diverging, absorbing, imposing a polarizationpattern, influencing a polarization pattern which, for example, may beby rotation of a polarization plane. Other ways to influence light canbe by influencing wave length, diverting the direction of a beam, forexample by using digital micro-mirror display (also known as DMD) or byusing field effect, influencing phase, interference techniques, whicheither block or transfer a portion of a beam of light, and the like.Activation of light valve elements, which are utilized by the disclosedtechnique, can be performed either electrically, magnetically oroptically. Commonly used light valve elements are liquid crystal basedelements, which either rotate or create and enforce a predeterminedpolarization axis.

In the present example, multiple aperture 804 includes two apertures 802_(R) and 802 _(L). The controller 834 further activates the multipleaperture 804, so as to alternately open apertures 802 _(R) and 802 _(L).In FIG. 20A, aperture 802 _(R) is open while aperture 802 _(L) is closedand in FIG. 20B, aperture 802 _(R) is closed while aperture 802 _(L) isopen.

Light rays, which reflect from various sections of the object 810, passthrough the currently open aperture (802 _(R) in FIG. 20A and 802 _(L)in FIG. 20B). Thereby, light rays 822 and 824 arrive from section 810Aof object 810, pass through aperture 802 _(R), and are detected bydetection element 808A, while light rays 826 and 828 arrive from section810D, pass through aperture 802 _(R) and are detected by detectionelement 808D. Hence, when aperture 802 _(R) is open, the system 800provides a right side view of the object 810.

With reference to FIG. 20B, when aperture 802 _(L) is open, light rays827 and 825 arrive from section 810A, pass through aperture 802 _(L),and are detected by detection element 808A, while light rays 821 and 823arrive from section 810D, pass through aperture 802 _(L), and aredetected by detection element 808D. Thereby, the system 800 provides aleft side view of the object 810.

The illumination unit 830 is a multi-color illumination unit, which canproduce light at a plurality of wavelengths. The controller 834 providesa sequence of illumination commands to the illumination unit 830, so asto produce a beam at a different predetermined wavelength, at each givenmoment. In the present example, the illumination unit is ared-green-blue (RGB) unit, which can produce a red light beam, a greenlight beam and a blue light beam. It is noted that illumination unit 830can be replaced with any other multi-color illumination unit, which canproduce either visible light, non-visible light or both, at any desiredwavelength combination (CYMG and the like).

Furthermore, illumination unit 830 can be a passive unit, where itreceives external commands to move from one wavelength to another, or itcan be an active unit, which changes wavelength independently andprovides an indication of the currently active wavelength to an externalcontroller. Illumination unit 830 of the present example is a passiveunit, which enhances the versatility of the system 800, by providing anywavelength sequence on demand.

The image detector 812 includes a plurality of detection elements 808A,808B, 808C and 808D. In accordance with one aspect of the disclosedtechnique, image detector 812 is a full range color detector, where eachof the detection elements is operative to detect light in a plurality ofwavelengths. In accordance with another aspect of the disclosedtechnique, the image detector 812 is a color segmented detector, wherethe detection elements are divided into groups, each operative to detectlight in a different range of wavelengths. One conventional type of suchdetectors includes a full range detection array, which is covered by acolor filter layer, where each detection element is covered by adifferent color filter. Accordingly, some of the detection elements arecovered with red filters, others are covered with green filters and therest are covered with blue filters.

The disclosed technique enhances the color resolution of systems, usingsuch color detectors. It will be appreciated by those skilled in the artthat a color segment detector of poor quality may exhibit a wavelength(color) overlap between the different detection elements. For example,when the filters are of poor quality, their filtering functions tend tooverlap such as the red filter also passes a small amount of eithergreen or blue light. Hence, the detection element behind the red filter,also detects that small amount of green or blue light, but provides anoutput measurement as a measurement of red light. Hence, the colordetector produces an image, which includes incorrect measurements of redlight (e.g. more than the actual red light, which arrived at thedetector) as result of that overlap. Accordingly, received informationof the inspected object is not valid.

In the disclosed technique, the illumination unit 830 produces asequence of non-overlapping illumination beams at predeterminedwavelengths (i.e., red, blue and green). As explained above, the colordetector detects an image, which includes incorrect measurements, as aresult of the wavelength (color) filtering overlap. Since theillumination unit 830 and the image acquisition process aresynchronized, the imaging system can process each of the acquiredimages, according to the actual light beam color, which was producedtherewith. For example, the illumination unit 830 produces blue lightillumination beam. At the same time the image detector 812 detects animage, which also includes actual light measurements in detectionelements, which are covered with green and red filters, due to thewavelength overlap. The imaging system can discard light measurements,which are received from detection elements, covered with color filters,which are not blue (e.g., red and green).

Such sequenced color illumination of the object, provides enhanced colorresolution, for color image detectors of poor quality, and obtains thevalid color images of the inspected object. System 800 can furtherinclude a stereoscopic display unit (not shown), coupled with controller834 for displaying a stereoscopic image of object 810.

Reference is further made to FIG. 21A, which is a schematic illustrationof a timing sequence, in which controller 834 (FIG. 20A) synchronizesthe operation of illumination unit 830, apertures 802 _(L) and 802 _(R),and image detector 812. Signal 840 represents the timing sequence of theleft aperture 802 _(L), Signal 842 represents the timing sequence of theright aperture 802 _(R). Signal 844 represents the timing sequence ofthe blue light beam, produced by the illumination unit 830. Signal 846represents the timing sequence of the green light beam, produced by theillumination unit 830. Signal 848 represents the timing sequence of thered light beam, produced by the illumination unit 830. Signal 841represents the timing sequence of the image detector 812, where eachimage is downloaded therefrom.

Timing sequence 841 rises every time any of the rises of sequences 844,846 and 848 intersect with a rise of either sequence 842 or sequence840. For example, rise 841 _(A) indicates a frame download of a bluelight-right aperture combination, rise 841 _(B) indicates a framedownload of a green light-right aperture combination, and rise 841 _(C)indicates a frame download of a red light-right aperture combination.Similarly, rise 841 _(D) indicates a frame download of a blue light-leftaperture combination, rise 841 _(E) indicates a frame download of agreen light-left aperture combination and rise 841 _(F) indicates aframe download of a red light-left aperture combination.

It is noted that for some light sources, the produced light beams do notcover the full range of visible light. For such light sources, themissing color components can be reconstructed (interpolated) taking intoconsideration the physiological assumption, that color reflectionresponse as a function of reflected angle, does not change much withangle.

Reference is further made to FIG. 22, which is a schematic illustrationof a method for operating system 800 of FIGS. 20A and 20B, operative inaccordance with another embodiment of the disclosed technique. In step870, a sequence of illumination beams at predetermined wavelengths isproduced. With reference to FIGS. 20A and 20B, controller 834 provides asequence of illumination commands to the illumination unit 830, which inturn produces different wavelength light beams, generally referenced832, at predetermined points in time, towards an object, generallyreferenced 810.

In step 872 right and left apertures are alternated. Light rays, whichreflect from various sections of the object 810, pass through thecurrently open aperture (802 _(R) in FIG. 20A and 802 _(L) in FIG. 20B).With reference to FIGS. 20A and 20B, controller 834 provides a sequenceof operating commands to the apertures 802 _(L) and 802 _(R).

In step 874, a plurality of frames, each for a selected aperture andwavelength combination is detected. Controller 834 operates the imagedetector 812 so as to detect a plurality of frames, each respective of aselected aperture and wavelength combination.

Light rays 822 and 824 (FIG. 20A) arrive from section 810A of object810, pass through aperture 802 _(R), and are detected by detectionelement 808A, while light rays 826 and 828 arrive from section 810D,pass through aperture 802 _(R) and are detected by detection element808D. It is noted that in the present example, an imaging element (notshown) is introduced in the vicinity of multiple aperture 804. Hence,when aperture 802 _(R) is open, the system 800 provides a right sideview of the object 810.

Light rays 827 and 825 (FIG. 20B) arrive from section 810A, pass throughaperture 802 _(L) and are detected by detection element 808A, whilelight rays 821 and 823 arrive from section 810D, pass through aperture802 _(L) and are detected by detection element 808D. Hence, whenaperture 802 _(L) is open, the system 800 provides a left side view ofthe object 810.

With reference to FIG. 21A, rise 841 _(A) provides a right side blueimage (reference 806 ^(R) _(B) of FIG. 20A), rise 841 _(B) provides aright side green image (reference 806 ^(R) _(G) of FIG. 20A), and rise841 _(C) provides a right side red image (reference 806 ^(R) _(R) ofFIG. 20A). Similarly, rise 841 _(D) provides a left side blue image(reference 806 ^(L) _(B) of FIG. 20B), rise 841 _(E) provides a leftside green image (reference 806 ^(L) _(G) of FIG. 20B), and rise 841_(F) provides a left side red image (reference 806 ^(L) _(R) of FIG.20B). With reference to FIGS. 20A and 20B, image detector 812 detectsthe plurality of frames, and provides right and left output video forimage processing.

In step 876, movement between the detector and the inspected organ, atselected frequencies is detected. This movement can be detected frommovement of the endoscope, by means of a movement detector, or byanalyzing the detected images, where different color images exhibitdifferent lines, with dramatic color shade changes. This information isutilized in the following step, for spatially correlating between imagesof different colors.

In step 878 a stereoscopic color image from the plurality of frames,according to their aperture origin is produced. With reference to FIGS.20A and 20B, the controller 834 stores the detected images in storageunit 836. Image processor 838 retrieves the detected images from thestorage unit 836, and constructs color stereoscopic images. Hence, thedisclosed technique provides an additional way for detecting a colorstereoscopic image, using a single image detector for both sides and allcolors.

Reference is further made to FIG. 21B, which is a schematic illustrationof another timing sequence, in which controller 834 (FIG. 20A)synchronizes the operation of illumination unit 830, apertures 802 _(L)and 802 _(R), and image detector 812. Signal 840′ represents the timingsequence of the left aperture 802 _(L). Signal 842′ represents thetiming sequence of the right aperture 802 _(R). Signal 844′ representsthe timing sequence of the blue light beam, produced by the illuminationunit 830. Signal 846′ represents the timing sequence of the green lightbeam, produced by the illumination unit 830. Signal 848′ represents thetiming sequence of the red light beam, produced by the illumination unit830. Signal 841′ represents the timing sequence of the image detector812, where each image is downloaded therefrom.

Timing sequence 841′ rises every time any of the rises of sequence 844′,846′ and 848′ intersects with a rise of either sequence 842′ or sequence840′. For example, rise 841′_(A) indicates a frame download of a bluelight-right aperture combination, rise 841′_(B) indicates a framedownload of a blue light-left aperture combination and rise 841′_(C)indicates a frame download of a green light-right aperture combination.Similarly, rise 841′_(D) indicates a frame download of a greenlight-left aperture combination, rise 841′_(E) indicates a framedownload of a red light-right aperture combination and rise 841′_(F)indicates a frame download of a blue light-left aperture combination.

Reference is further made to FIG. 23, which is a schematic illustrationof a timing scheme, for operating system 800 of FIGS. 20A and 20B, inaccordance with a further embodiment of the disclosed technique. Signal850 represents the timing sequence of the left aperture 802 _(L). Signal852 represents the timing sequence of the right aperture 802 _(R).Signal 854 represents the timing sequence of the blue light beam. Signal856 represents the timing sequence of the green light beam. Signal 858represents the timing sequence of the red light beam. Signal 851represents the timing sequence of the image detector 812, where eachimage is downloaded therefrom. As can be seen in FIG. 23, the timingscheme is asymmetric, where the green light beam is activated for a timeperiod which is twice the time period of either the red light beam orthe blue light beam. Signal 851 corresponds to this arrangement andprovides a green image download rise (references 851 _(B) and 851 _(E)),after a time period which is twice as long with comparison to red imagedownload rises (references 851 _(C) and 851 _(F)) or blue image downloadrises (references 851 _(A) and 851 _(D)).

Reference is further made to FIG. 24, which is a schematic illustrationof a timing scheme, for operating system 800 of FIGS. 20A and 20B, inaccordance with another embodiment of the disclosed technique. Signal860 represents the timing sequence of the left aperture 802 _(L). Signal862 represents the timing sequence of the right aperture 802 _(R).Signal 864 represents the timing sequence of the magenta light beam.Signal 866 represents the timing sequence of the yellow light beam.Signal 868 represents the timing sequence of the cyan light beam. As canbe seen in FIG. 24, the timing scheme addresses an alternate wavelengthscheme and is also asymmetric.

It is noted that a mechanical multi-wavelength illumination unit such asdescribed in the prior art, can be used for implementing the disclosedtechnique. However, such a system significantly reduces the capabilityof the user to control illumination duration, wavelength ratio anddetection timing, such as described herein above.

The disclosed technique incorporates even more advanced aspects, whichprovide automatic image translation correction, based on correlationbetween the two detected images. When the endoscope is handheld, it issubjected to the vibration of the human hand, which is in the order of10 Hz, at an angular amplitude of 1 degree. This phenomenon causes ablur of areas, where different colors intersect, and is also known asthe “between color field blur” effect. It is noted that any movementbetween the image detector and the inspected organ can cause thisphenomenon, provided it occurs at particular frequencies, defined by thestructure and the manner of operation of the system.

With reference to FIGS. 20A and 20B, since the information retrievedfrom image detector 812 relates to specific colors, then controller 834can correlate between such single color images to determine the ΔX andΔY to the subsequent color, and hence compose and produce an un-blurredcolor image. Due to the vibrations of the human hand, while imagedetector 812 is substantially stationary relative to object 810, thedisplayed stereoscopic image of object 810 is blurred. In order tomitigate this problem, and provide a blur-free stereoscopic image ofobject 810 to the viewer, movement detector 230 (FIG. 2), isincorporated with system 200, and movement detector 814 is incorporatedwith system 800.

Reference is now made to FIGS. 25A, 25B, 25C, 26A, 26B and 26C and againto FIG. 2. FIG. 25A is a schematic illustration of an object, generallyreferenced 766, and a sensor assembly generally referenced 768, when thesensor assembly is located at an initial position with respect to theobject. FIG. 25B is a schematic illustration of the object and thesensor assembly of FIG. 25A, when the sensor assembly has moved to a newposition. FIG. 25C is a schematic illustration of the object and thesensor assembly of FIG. 25A, when the sensor assembly has moved toanother position. FIG. 26A is a schematic illustration of a detectedimage, generally referenced 770, as detected by sensor assembly of FIG.25A, and a respective displayed image, generally referenced 772, inaccordance with a further embodiment of the disclosed technique. FIG.26B is a schematic illustration of a detected image, generallyreferenced 780, as detected by sensor assembly of FIG. 25B, and arespective displayed image, generally referenced 774. FIG. 26C is aschematic illustration of a detected image, generally referenced 782, asdetected by the sensor assembly of FIG. 25C, and a respective displayedimage, generally referenced 776.

The foregoing description relates to one aspect of the disclosedtechnique, in which a stereoscopic image of an object is captured by asensor array through a lenticular lens layer (i.e., each captured imageincludes all the primary colors of the color palette, such as RGB, CYMG,and the like). It is noted that the movement is determined such that ithas a constant average (e.g., vibrating about a certain point).

With reference to FIGS. 25A and 26A, the center of sensor assembly 768is located at a point O₁ relative to object 766. Sensor assembly 768detects detected image 770 (FIG. 26A) of object 766, where the detectedimage 770 is composed for example, of four hundred pixels (i.e., a 20×20matrix). Each pixel is designated by P_(m,n) where m is the row and n isthe column of detected image 770. For example, pixel 778 _(1,1) islocated in the first row and the first column of detected image 770,pixel 778 _(1,2) is located in the first row and the second column, andpixel 778 _(20,20) is located in row twenty and column twenty. Processor208 selects pixels 778 _(3,3) through 778 _(18,18) (i.e., a total of16×16=256 pixels) to display the sub-matrix 772 on stereoscopic display214 (FIG. 2), while the center of sensor assembly 768 is located atpoint O₁.

With reference to FIGS. 25B and 26B, due to the vibrations of the humanhand, the center of sensor assembly 768 has moved to a point O₂ relativeto object 766. Point O₂ is located a distance ΔX₁ to the right of pointO₁ and a distance ΔY₁ below point O₁. In this case the length of ΔX₁ isequal to the horizontal width of two pixels of detected image 780, andthe length ΔY₁ is equal to the vertical height of minus two pixels ofdetected image 780. Movement detector 230 detects the movement of sensorassembly 768 from point O₁ to point O₂, and sends a signal respective ofthis movement, to processor 208.

With reference to FIG. 26B, the image of the object section that wascaptured by sub-matrix 772, is now captured by a sub-matrix 774, whichis shifted two pixels up and two pixels to the left. Hence, displayingsub-matrix 774, compensates for the movement of sensor assembly 768. Forthis purpose, processor 208 selects pixels 778 _(1,1) through 778_(16,16) of detected image 780, for sub-matrix 774. Despite the movementof sensor assembly 768, the images of sub-matrices 772 and 774 aresubstantially of the same area, and therefore the user does not realizethat sensor assembly 768 has moved from point O₁ to point O₂.

With reference to FIGS. 25C and 26C, the center of sensor assembly 768has moved from point O₁ to a point O₃ relative to object 766. Point O₃is located a distance ΔX₂ to the left of point O₁ and a distance ΔY₂above point O₁. In this case the length of ΔX₂ is equal to thehorizontal of minus two pixels of detected image 782, and the length ΔY₂is equal to the vertical height of one pixel of detected image 782.Movement detector 230 detects the movement of sensor assembly 768 frompoint O₁ to point O₃, and sends a signal respective of this movement, toprocessor 208.

With reference to FIG. 26C, the image of the object section that wascaptured by sub-matrix 772, is now captured by a sub-matrix 776, whichis shifted one pixel up and two pixels to the left. Hence, displayingsub-matrix 774, compensates for the movement of sensor assembly 768 twopixels to the left and one pixel up. For this purpose, processor 208selects pixels 778 _(5,4) through 778 _(20,19) of detected image 782,for sub-matrix 776. Despite the movement of sensor assembly 768, theimages of displayed images 772 and 776 are identical, and therefore theuser does not realize that sensor assembly 768 has moved from point O₁to point O₃. Therefore, by incorporating movement detector 230 withsensor assembly 768, the viewer views a blur-free stereoscopic colorimage of object 766, despite the vibrations of sensor assembly 768caused by the human hand.

It is noted that processor 208 processes the detected images 780 and782, if the dimensions ΔX₁, ΔX₂, ΔY₁ and ΔY₂ are of the order of A, theamplitude of vibrations of the human hand and in the appropriatefrequency. In general, processor 208 performs the compensation process,between a plurality of captured images, as long as the detectedmovement, is maintained about a certain average point (X_(AVERAGE),Y_(AVERAGE)). When one of the average values X_(AVERAGE) and Y_(AVERAGE)changes, then processor 208 initiates a new compensation process aroundthe updated average point, accordingly.

Reference is now made to FIGS. 25D, 25E, 25F, 27A, 27B, 27C, 27D, 27E,27F and again to FIGS. 20A, 20B, 25A, 25B and 25C. FIG. 25D is aschematic illustration of the object and the sensor assembly of FIG.25A, when the sensor assembly has moved to a further new position. FIG.25E is a schematic illustration of the object and the sensor assembly ofFIG. 25A, when the sensor assembly has moved to another new position.FIG. 25F is a schematic illustration of the object and the sensorassembly of FIG. 25A, when the sensor assembly has moved to a furthernew position. FIG. 27A is a schematic illustration of a sub-matrix,generally referenced 1064, in accordance with another embodiment of thedisclosed technique, when the sensor assembly is at a locationillustrated in FIG. 25A. FIG. 27B is a schematic illustration of asub-matrix, generally referenced 1066, when the sensor assembly is at alocation illustrated in FIG. 25B. FIG. 27C is a schematic illustrationof a sub-matrix, generally referenced 1068, when the sensor assembly isat a location illustrated in FIG. 25C. FIG. 27D is a schematicillustration of a sub-matrix, generally referenced 1070, when the sensorassembly is at a location illustrated in FIG. 25D. FIG. 27E is aschematic illustration of a sub-matrix, generally referenced 1072, whenthe sensor assembly is at a location illustrated in FIG. 25E. FIG. 27Fis a schematic illustration of a sub-matrix, generally referenced 1074,when the sensor assembly is at a location illustrated in FIG. 25F.

Image processor 838 (FIG. 20A), selects each of sub-matrices 1064, 1066and 1068 from detected images 1052, 1054 and 1056, respectively, asdescribed herein above in connection with FIGS. 26A, 26B and 26C.Analogously, image processor 838 selects each of sub-matrices 1070, 1072and 1074 from detected images 1058, 1060 and 1062, respectively, whenthe center of sensor assembly 768 is directed to each of the points O₄,O₅, and O₆, respectively. For example, when the center of sensorassembly 768 is directed to point O₄, which is located to the right andabove point O₁, image processor 838 selects sub-matrix 1070 (FIG. 27D).When the center of sensor assembly 838 is directed to point O₅ directlybelow point O₁, image processor 838 selects sub-matrix 1072 (FIG. 27E).When the center of sensor assembly 838 is directed to point O₆ directlyabove point O₁, image processor 838 selects sub-matrix 1074 (FIG. 27F).

In the following description, object 810 (FIGS. 20A and 20B) and object766 (FIG. 25A) are used interchangeably, although they both representthe same object. Object 810 is described in connection with multipleaperture 804 and illumination unit 830, while object 766 is described inconnection with the location of sensor assembly 768 relative thereto. Itis noted that during the time interval in which the opening of multipleaperture 804 switches from aperture 802 _(R) (FIG. 20A), to aperture 802_(L) (FIG. 20B), sensor assembly 768 moves relative to object 766, dueto the vibrations of the human hand. Thus, for example, sub-matrix 1064(FIG. 27A) represents a right view image of object 810 corresponding tothe image which image processor 838 captures, when aperture 802 _(R) isopen. On the other hand, sub-matrix 1066 (FIG. 27B) represents a leftview image of object 766, when aperture 802 _(L) is open.

Furthermore, the color of detected images 1052, 1054, 1056, 1058, 1060,and 1062 changes as described herein above for example in connectionwith FIG. 21B. Image processor 838 receives download image 841′_(A), andselects sub-matrix 1064 (FIG. 27A), which is a right view image ofobject 766 (FIG. 25A) in blue, when the center of sensor assembly 768 isdirected to point O₁.

While multiple aperture 804 switches to aperture 802 _(L), the center ofsensor assembly 768 (FIG. 25B) directs to point O₂ (FIG. 25B), and imageprocessor 838 receives download image 841′_(B). Since the center ofsensor assembly 768 is directed to point O₂ (FIG. 25B), then imageprocessor 838 selects sub-matrix 1066 (FIG. 27B) which represents a leftview image of object 810 in blue. Analogously, sub-matrix 1068 (FIG.27C) represents a green right view image of object 766 (download image841′_(C)), when the center of sensor assembly 768 is directed to pointO₃ (FIG. 25C). Sub-matrix 1070 (FIG. 27D) represents a green left viewimage of object 766 (download image 841′_(D)), when the center of sensorassembly 768 directs to point O₄ (FIG. 25D). Sub-matrix 1072 (FIG. 27E)represents a red right view image of object 766 (download image841′_(E)), when the center of sensor assembly 768 directs to point O₅(FIG. 25E). Sub-matrix 1074 (FIG. 27F) represents a red left view imageof object 766 (download image 841′_(F)), when the center of sensorassembly 768 directs to point O₆ (FIG. 25F).

According to FIG. 21A, a stereoscopic display unit (not shown) displayssub-matrices 1064, 1066, 1068, 1070, 1072 and 1074 in sequence.Sub-matrices 1064, 1068 and 1072 are the right side views ofsubstantially the same area of object 766, which together compose aright side color image of the object 766. Sub-matrices 1066, 1070 and1074 are the left side views of substantially the same area of object766, which together compose a left side color image of the object 766.The stereoscopic display unit alternately displays the right view imageand the left view image of substantially the same area of object 766.Thus, system 800 maintains a stable image of object 766, which does notexhibit any change in the location of object 766 as displayed on thestereoscopic display unit, despite the movement of sensor assembly 768due to the vibrations of the human hand.

For example, image processor 838 selects sub-matrices 1064, 1068 and1072 (FIGS. 27A, 27C and 27E, respectively), and the stereoscopicdisplay (not shown), sequentially displays the same image in blue, greenand red, respectively. Thus, the stereoscopic display presents a stableright side image of the object in full color, to the right eye.Similarly, the stereoscopic display sequentially displays sub-matrices1066, 1070 and 1074 (FIGS. 27B, 27D and 27F, respectively), wherein thecolor of each sub-matrix sequentially changes from blue to green to red,respectively. In this manner, the stereoscopic display presents a stableleft side image of the object in full color, to the left eye. Thus, theuser views a stable full color stereoscopic image of the object, despitethe movement of the endoscope due to the vibrations of the human hand.

It is noted that an RGB timing scheme can be employed. In this case, thestereoscopic display displays the sub-matrices in a sequence ofright-red, left-green, right-blue, left-red, right-green and left-blue.

It is noted that the sequence of FIGS. 27A, 27B, 27C, 27D, 27E and 27Fis cyclically repeated during the imaging process of the object. Othertiming schemes can be employed where the download image trigger signalis used for acquiring a reading from movement detector 814, for thedetected image. Examples for such timing schemes are illustrated inFIGS. 23, 24, and 21A.

According to another aspect of the disclosed technique, the locationsfrom which the three-dimensional object is viewed from the right sideand from the left side thereof, are further separated. Thus, thedifference between the right side view image and the left side viewimage is substantially increased and the stereoscopic notion produced bythe two images is substantially enhanced.

Reference is now made to FIGS. 28A and 28B. FIG. 28A is a schematicillustration of a stereoscopic imaging apparatus, generally referenced1100, constructed and operative in accordance with a further embodimentof the disclosed technique. FIG. 28B is a schematic illustration of theapparatus of FIG. 28A, in another mode of imaging.

Apparatus 1100 includes a periscopic assembly 1102, an optical assembly1104, a lenticular lens layer 1106 and a light sensor array 1108.Periscopic assembly 1102 includes a right mirror 1110, a left mirror1112, a right center mirror 1114 and a left center mirror 1116.Lenticular lens layer 1106 and light sensor array 1108 are similar tolenticular lens layer 104 and light sensor array 102, respectively, asdescribed herein above in connection with FIG. 1. However, lenticularlens layer 1106 is positioned in an orientation opposite to thatillustrated in FIG. 1. Periscopic assembly 1102 is located between athree-dimensional object 1118 and optical assembly 1104. Opticalassembly 1104 is located between periscopic assembly 1102 and lenticularlens layer 1106.

With reference to FIG. 28A, right mirror 1110 receives a light beam1120A, which is a right side view of the right side of three-dimensionalobject 1118. Right mirror 1110 reflects light beam 1120A, as a lightbeam 1120B. Right center mirror 1114 reflects light beam 1120B towardoptical assembly 1104, as a light beam 1120C. Optical assembly 1104directs a light beam 1120D to a lenticular element 1128 of lenticularlens layer 1106. Lenticular element 1128 focuses light beam 1120D on asensor 1130 of light sensor array 1108. Light sensor array 1108 detectsthe right side view image of three-dimensional object 1118 and providesa respective signal to a processor, such as processor 208 (FIG. 2), viaan interface, such as interface 210.

Left mirror 1112 receives a light beam 1122A, which is a left side viewof the right side of three-dimensional object 1118. Left mirror 1112reflects light beam 1122A, as a light beam 1122B. Left center mirror1116 reflects light beam 1122B toward optical assembly 1104, as a lightbeam 1122C. Optical assembly 1104 directs a light beam 1122D tolenticular element 1128 of lenticular lens layer 1106. Lenticularelement 1128 focuses light beam 1122D on a sensor 1132 of light sensorarray 1108.

With reference to FIG. 28B, left mirror 1112 receives a light beam1124A, which is a left side view of the left side of three-dimensionalobject 1118. Left mirror 1112 reflects light beam 1124A, as a light beam1124B. Left center mirror 1116 reflects light beam 1124B toward opticalassembly 1104, as a light beam 1124C. Optical assembly 1104 directs alight beam 1124D to a lenticular element 1134 of lenticular lens layer1106. Lenticular element 1134 focuses light beam 1124D on a sensor 1136of light sensor array 1108.

Right mirror 1110 receives a light beam 1126A, which is a right sideview of the left side of three-dimensional object 1118. Right mirror1110 reflects light beam 1126A, as a light beam 1126B. Right centermirror 1114 reflects light beam 1126B toward optical assembly 1104, as alight beam 1126C. Optical assembly 1104 directs a light beam 1126D tolenticular element 1134 of lenticular lens layer 1106. Lenticularelement 1134 focuses light beam 1126D on a sensor 1138 of light sensorarray 1108.

It is noted that right mirror 1110 and right center mirror 1114 togetheroperate similar to a periscope. Likewise, left mirror 1112 and leftcenter mirror 1116 together operate similar to a periscope. Right mirror1110 and left mirror 1112 are located substantially apart relative to anaxis which is perpendicular to lenticular lens layer 1106 and whichpasses through the junction of right center mirror 1114 and left centermirror 1116. Hence, right mirror 1110 detects a right side view ofthree-dimensional object 1118, which is substantially different than theleft side view thereof, detected by left mirror 1112. Thus, therespective light detecting elements of light sensor array 1108 receivelight beams respective of the right side view and the left side view ofthree-dimensional object 1118, which are more distinct than in the caseof FIG. 1. Hence, apparatus 1100 can provide a sharper stereoscopicimage of three-dimensional object 1118, than an apparatus similar toapparatus 200 (FIG. 2).

According to another aspect of the disclosed technique, a light valvealternately differentiates between images of a three-dimensional objectreceived from different directions, and alternately provides theseimages to an image detector. Thus, the image detector alternatelydetects images of the three-dimensional object, from different sidesthereof.

Reference is now made to FIGS. 29A and 29B. FIG. 29A is a schematicillustration of a stereoscopic imaging apparatus in a right sidedetection mode, generally referenced 1150, constructed and operative inaccordance with another embodiment of the disclosed technique. FIG. 29Bis a schematic illustration of the apparatus of FIG. 29A, in a left sidedetection mode.

Apparatus 1150 includes a periscope assembly 1152, a multiple aperture1154, an optical assembly 1156, a light sensor array 1158, a controller1160, a storage unit 1162 and an image processor 1164. Periscopeassembly 1152 includes a right mirror 1166, a left mirror 1168, a rightcenter mirror 1170 and a left center mirror 1172. Multiple aperture 1154includes a right aperture 1174 _(R) and a left aperture 1174 _(L).Multiple aperture 1154 is similar to multiple aperture 804, as describedherein above in connection with FIG. 20A.

Periscope assembly 1152 is located between a three-dimensional object1176 and multiple aperture 1154. Multiple aperture 1154 is locatedbetween periscope assembly 1152 and optical assembly 1156. Multipleaperture 1154 is located substantially close to periscope assembly 1152.Optical assembly 1156 is located between multiple aperture 1154 andlight sensor array 1158. Multiple aperture 1154, light sensor array1158, controller 1160, storage unit 1162 and image processor 1164, areinterconnected via a bus 1186. Controller 1160 controls multipleaperture 1154, such that right aperture 1174 _(R) and left aperture 1174_(L) alternately open and close.

With reference to FIG. 29A, controller 1160 controls multiple aperture1154, such that right aperture 1174 _(R) is open and left aperture 1174_(L) is closed. Right mirror 1166 receives light beams 1178 and 1180 asreflected from three-dimensional object 1176. Left mirror 1168 receiveslight beams 1182 and 1184 as reflected from three-dimensional object1176. Right center mirror 1170 reflects the reflection of light beams1178 and 1180 toward right aperture 1174 _(R). Since right aperture 1174_(R) is open, light beams 1178 and 1180 pass through right aperture 1174_(R), reach light sensor array 1158 through optical assembly 1156.Controller 1160 enables light sensor array 1158 to detect a right sideview image of three-dimensional object 1176, according to the state ofmultiple aperture 1154 (i.e., when right aperture 1174 _(R) is open).Controller 1160 stores this right side view image in storage unit 1162.Since left aperture 1174 _(L) is closed, light beams 1182 and 1184 whichare reflected by left mirror 1168 and left center mirror 1172, areblocked and do not reach light sensor array 1158.

With reference to FIG. 29B, controller 1160 controls multiple aperture1154, such that right aperture 1174 _(R) is closed and left aperture1174 _(L) is open. Light beams 1182 and 1184 reach light sensor array1158, after reflections from left mirror 1168 and left center mirror1172 and after passing through left aperture 1174 _(L) and opticalassembly 1156. Controller 1160 enables light sensor array 1158 to detecta left side view image of three-dimensional object 1176, according tothe state of multiple aperture 1154 (i.e., when left aperture 1174 _(L)is open). Controller 1160 stores this left side view image in storageunit 1162. Since right aperture 1174 _(R) is closed, light beams 1178and 1180 which are reflected by right mirror 1166 and right centermirror 1170, are blocked and do not reach light sensor array 1158.Controller 1160 alternately stores right and left side view images ofthree-dimensional object 1176 in storage unit 1162, according to thestate of multiple aperture 1154. Image processor 1164 produces a videosignal for a stereoscopic display, such as stereoscopic display 214(FIG. 2), by retrieving these images from storage unit 1162 andprocessing them.

Alternatively, multiple aperture 1154 is located betweenthree-dimensional object 1176 and periscope assembly 1152. In this case,right mirror 1166 receives a right side view image of three-dimensionalobject 1176 only when right aperture 1174 _(R) is open. Similarly, leftmirror 1168 receives the left side view image of three-dimensionalobject 1176, only when left aperture 1174 _(L) is open. Multipleaperture 1154 is located substantially close to periscope assembly 1152.

Alternatively, an illuminator similar to illuminator 830 (FIG. 20A) isemployed, in order to sequentially illuminate the three-dimensionalobject by red, green and blue light. The operation of the illuminator iscontrolled by a controller. In this case, when the right aperture isopen, the light sensor array sequentially detects the right side viewimage of the three-dimensional object, in red, green and blue colors.The controller sequentially stores the red, green and blue frames of theright side view image of the object in the storage unit. When the leftaperture is open, the light sensor array sequentially detects the leftside view image of the three-dimensional object, in red, green and bluecolors. The controller sequentially stores the red, green and blueframes of the left side view image of the object in the storage unit.The image processor, then produces a video signal respective of thefull-color right side view image and the full-color left side view imageof the object and a stereoscopic display displays a stereoscopic imageof the object in full color.

It is noted that the illuminator can emit light in the visible range ofwavelengths, as well as in the invisible range of wavelengths. Inaddition, the wavelength of light emitted by the illuminator can begenerally discrete (e.g., green light is emitted either at 500 nm, 525nm, 542 nm, and so on).

According to another aspect of the disclosed technique, imagedifferentiation is performed sequentially by filtering light atdifferent sets of wavelengths for each of the right side image and theleft side image. According to one embodiment two different lightfilters, a right side filter and a left side filter, are placed betweena three-dimensional object and an image detector. The right side filteradmits light at one set of ranges of wavelengths and the left sidefilter admits light at another set of ranges of wavelengths. The twosets of ranges of wavelengths are mutually exclusive. The right sidefilter receives a right side view image of the three-dimensional objectand the left side filter receives a left side view image of thethree-dimensional object.

The three-dimensional object is sequentially illuminated with two groupsof wavelengths. The first group of wavelengths is included only in theset of ranges of wavelengths of right side filter. The second group ofwavelengths is included only in the set of ranges of wavelengths of theleft side filter.

When the object is illuminated with first group of wavelengths, theright side filter passes a right side image to the image detector, whilethe left side filter blocks these wavelengths. Similarly, when theobject is illuminated with second group of wavelengths, the left sidefilter passes a left side image to the image detector, while the rightside filter blocks these wavelengths.

Reference is now made to FIGS. 30A and 30B. FIG. 30A is a schematicillustration of a stereoscopic imaging apparatus in a right side filtermode, generally referenced 1200, constructed and operative in accordancewith a further embodiment of the disclosed technique. FIG. 30B is aschematic illustration of the apparatus of FIG. 30A, in a left sidefilter mode.

Apparatus 1200 includes a right side filter 1202, a left side filter1204, a periscope assembly 1206, an optical assembly 1208, a lightsensor array 1210, an illuminating unit 1240, a controller 1216, astorage unit 1218 and an image processor 1220. Periscope assembly 1206includes a right mirror 1222, a left mirror 1224, a right center mirror1226 and a left center mirror 1228. Illuminating unit 1240 includesilluminators 1212 and 1214. Right side filter 1202 is a light filter,which admits light only in red, green and blue ranges of wavelengthsΔR₁, ΔG₁ and ΔB₁, respectively. Left side filter 1204 is a light filterwhich admits light only in red, green and blue ranges of wavelengthsΔR₂, ΔG₂ and ΔB₂, respectively, where the ranges of wavelengths ΔR₁, ΔG₁and ΔB₁ and the ranges of wavelengths ΔR₂, ΔG₂ and ΔB₂ do not overlap.Illuminator 1212 emits light at the group of wavelengths R₁, G₁ and B₁(i.e., RGB₁), which are is included in the ranges of wavelengths ΔR₁,ΔG₁ and ΔB₁ and excluded from the ranges of wavelengths ΔR₂, ΔG₂ andΔB₂. Illuminator 1214 emits light at the group of wavelengths R₂, G₂ andB₂ (i.e., RGB₂), which is included in the ranges of wavelengths ΔR₂, ΔG₂and ΔB₂ and excluded from the ranges of wavelengths ΔR₁, ΔG₁ and ΔB₁.Thus, illuminating unit 1240 sequentially emits light at the group ofwavelengths RGB₁ and RGB₂. It is noted that R₁ refers to one wavelengthor more, which are included in the red wavelength range R, arrangedcontinuously, discretely or in a mixed fashion. The same applies to R₂with respect to R, G₁ and G₂ with respect to the green wavelength rangeG and B₁ and B₂ with respect to the blue wavelength range B. Thisapplies to all types of wavelength differentiators which shall bedisclosed further below.

In the example set forth in FIGS. 30A and 30B, each of illuminators 1212and 1214 emits light in the visible range (i.e., different wavelengthsof red, green and blue). Accordingly, each of right side filter 1202 andleft side filter 1204 admits light in different ranges of red, green andblue, which include the red, green and blue wavelengths of right sidefilter 1202 and left side filter 1204, respectively. Alternatively, eachof the illuminators emits light in the invisible range, such asinfrared, and the like, and each of the right side filter and the leftside filter admits light in different ranges of wavelengthscorresponding to the wavelengths of light emitted by the illuminators.

Right side filter 1202 and left side filter 1204 are located between athree-dimensional object 1230 and periscope assembly 1206. Opticalassembly 1208 is located between periscope assembly 1206 and lightsensor array 1210. Light sensor array 1210, controller 1216, storageunit 1218 and image processor 1220 are interconnected via a bus 1268.Illuminating unit 1240 is coupled with controller 1216.

With reference to FIG. 30A, controller 1216 controls illuminating unit1240, to illuminate three-dimensional object 1230 at the group ofwavelengths RGB₁. Three-dimensional object 1230 reflects the light atthe group of wavelengths RGB₁ toward right side filter 1202, as lightbeams 1232 and 1234 and toward left side filter 1204, as light beams1236 and 1238. Light beams 1232 and 1234 include information respectiveof a right side view image of three-dimensional object 1230. Light beams1236 and 1238 include information respective of a left side view imageof three-dimensional object 1230. Since right side filter 1202 admitslight in the ranges of wavelengths ΔR₁, ΔG₁ and ΔB₁, and the group ofwavelengths RGB₁ is included in the ranges of wavelengths ΔR₁, ΔG₁ andΔB₁, light beams 1232 and 1234 pass through right side filter 1202 andreach right mirror 1222.

Right center mirror 1226 reflects the reflection of light beams 1232 and1234 from right mirror 1222, to optical assembly 1208. Optical assembly1208 focuses light beams 1232 and 1234 on light sensor array 1210. Thus,when illuminating unit 1240 emits light at the group of wavelengths RGB₁the right side view image of three-dimensional object 1230 at the groupof wavelengths RGB₁ reaches light sensor array 1210. It is noted thatsince the group of wavelengths RGB₁ is not included in any of the rangesof wavelengths at which left side filter 1204 admits light, left sidefilter 1204 blocks light beams 1236 and 1238, and that the left sideview image of three-dimensional object 1230 does not reach light sensorarray 1210 at this stage. Controller 1216 stores this right side viewimage of three-dimensional object 1230, in storage unit 1218.

With reference to FIG. 30B, controller 1216 controls illuminating unit1240, to illuminate three-dimensional object 1230 at the group ofwavelengths RGB₂. Three-dimensional object 1230 reflects the light atthe group of wavelengths RGB₂ toward left side filter 1204, as lightbeams 1264 and 1266 and toward right side filter 1202, as light beams1260 and 1262. Light beams 1264 and 1266 include information respectiveof a left side view image of three-dimensional object 1230. Light beams1260 and 1262 include information respective of a right side view imageof three-dimensional object 1230. Since left side filter 1204 admitslight in the ranges of wavelengths ΔR₂, ΔG₂ and ΔB₂, and the group ofwavelengths RGB₂ is included in the ranges of wavelengths ΔR₂, ΔG₂ andΔB₂, light beams 1264 and 1266 pass through left side filter 1204 andreach left mirror 1224.

Left center mirror 1228 reflects the reflection of light beams 1264 and1266 from left mirror 1224, to optical assembly 1208. Optical assembly1208 focuses light beams 1264 and 1266 on light sensor array 1210. Thus,when illuminating unit 1240 emits light at the group of wavelengths RGB₂the left side view image of three-dimensional object 1230 at the groupof wavelengths RGB₂ reaches light sensor array 1210. Since the group ofwavelengths RGB₂ is not included in any of the ranges of wavelengths atwhich right side filter 1202 admits light, right side filter 1202 blockslight beams 1260 and 1262, and the right side view image ofthree-dimensional object 1230 does not reach light sensor array 1210 atthis stage. Controller 1216 stores this left side view image ofthree-dimensional object 1230, in storage unit 1218.

Image processor 1220 retrieves the right side and the left side viewimages of three-dimensional object 1230, from storage unit 1218 andproduces stereoscopic images of three-dimensional object 1230, byprocessing the right side and the left side view images. It is notedthat in the example set forth in FIGS. 30A and 30B, light sensor array1210 is a color light detector.

Alternatively, in a system which includes a full range light sensorarray, the controller controls the operation of the illuminating unit,to sequentially emit light at individual groups of wavelengths R₁, R₂,G₁, G₂, B₁ and B₂. In this case, the right side filter admits a sequenceof right side view images of the three-dimensional object, in each ofthe ranges of wavelengths R₁, G₁ and B₁, and then the left side filteradmits a sequence of left side view images of the three-dimensionalobject, in each of the wavelengths R₂, G₂ and B₂. For each cycle in theillumination sequence, the controller enables the light sensor array todetect six images of the three-dimensional object. Three of these imagesare right side view images, each at a different one of the groups ofwavelengths R₁, G₁ and B₁. The other three images are left side viewimages, each at a different one of the groups of wavelengths R₂, G₂ andB₂. It is noted that other sequences of R₁, R₂, G₁, G₂, B₁ and B₂, aswell as other divisions of light (e.g., CYMG₁ and CYMG₂) are applicable.

In the example set forth in FIGS. 30A and 30B, system 1200 isconstructed to operate in the visible range. Alternatively, a systemaccording to another embodiment can be constructed to operate in theinvisible range, such as infrared (far and near), ultra-violet, and thelike.

Alternatively, each of the illuminators 1212 and 1214 can includeseveral light sources, each at a different group of wavelengths (e.g.,an illuminator for each of ΔR₁, ΔG₁, ΔB₁, ΔR₂, ΔG₂ and ΔB₂). It is notedthat this aspect of the disclosed technique, can be limited to a singlerange for each channel (i.e., blue for the right channel and red for theleft channel).

Alternatively, the right side filter and the left side filter arelocated between the periscope assembly and the optical assembly. In thiscase, the right side filter receives a right side view image of thethree-dimensional object from the right center mirror, and the left sidefilter receives a left side view image of the three-dimensional objectfrom the left center mirror.

Alternatively, a rotating disk is placed in front of the periscopeassembly and an illuminator constantly emits light. Half of the rotatingdisk is transparent and the other half is opaque. Thus, as the rotatingdisk rotates, the periscope assembly alternately receives the right sideand the left side view images of the three-dimensional object anddirects these images to the light sensor array.

With reference to FIG. 30A, a partially-transparent rotating diskreplaces right side filter 1202 and left side filter 1204. Furthermore,an illuminator which provides light in a predetermined range ofwavelengths, replaces illuminating unit 1240. The partially-transparentrotating disk is divided into a transparent portion and an opaqueportion, as described herein below in connection with FIGS. 39A and 39B.

When the transparent portion of the partially-transparent rotating diskis located above the right mirror, the right mirror receives a rightside view image of the three-dimensional object and the opaque portionof the partially-transparent rotating disk blocks the light to the leftmirror. When the transparent portion of the partially-transparentrotating disk is located above the left mirror, the left mirror receivesa left side view image of the three-dimensional object and the opaqueportion of the partially-transparent rotating disk blocks the light tothe right mirror. The controller enables the light sensor array toalternately detect a right side view image and a left side view image ofthe three-dimensional object, according to the position of thetransparent portion relative to the right mirror and the left mirror.The controller alternately stores the right side view images and theleft side view images in the storage unit. The image processorconcurrently retrieves the right side view images and left side viewimages of the three-dimensional object, processes these images andprovides a respective video signal to a stereoscopic display, such asstereoscopic display 214 (FIG. 2).

Alternatively, a rotating disk is placed in front of the periscopeassembly and a multi-wavelength illuminator sequentially emits light indifferent ranges of wavelengths. Half of the rotating disk istransparent and the other half is opaque. As the rotating disk rotates,the periscope assembly receives a sequence of right side and left sideview images of the three-dimensional object, in different ranges ofwavelengths and directs these images to the light sensor array. Thisembodiment is similar to the embodiments described herein above inconnection with FIGS. 14B, 20A and 20B.

With reference to FIG. 30A, a partially-transparent rotating diskreplaces right side filter 1202 and left side filter 1204. Furthermore,a multi-wavelength illuminator which sequentially emits light indifferent ranges of wavelengths, replaces illuminating unit 1240. Halfof the partially-transparent rotating disk is transparent and the otherhalf is opaque. The partially-transparent rotating disk is coupled withthe controller. The controller controls the operation of themulti-wavelength illuminator, to sequentially emit light in differentranges of wavelengths. As the partially-transparent rotating diskrotates, the transparent portion alternately covers the right mirror andthe left mirror. The controller enables the light sensor array to detecteach of the right side and the left side view images of thethree-dimensional object, in these different ranges of wavelengths,according to the angular position of the partially-transparent rotatingdisk and the state of the multi-wavelength illuminator. The controllerstores these images in the storage unit.

For example, when the multi-wavelength illuminator sequentiallyilluminates the three-dimensional object in red, green and blue (i.e.,RGB), and the transparent portion is located above the right mirror, thelight sensor array detects a sequence of images in red, green and blue.According to the position of the partially-transparent rotating disk andthe state of the multi-wavelength illuminator, the controller determinesthat these images are right side view images of the three-dimensionalobject, in red, green and blue, respectively. The controller storesthese images in the storage unit.

The light sensor array detects right side view images when thetransparent portion is located above the right mirror. The light sensorarray detects left side view images when the transparent portion islocated above the left mirror. The controller tags each of these imagesaccording to the state of multi-wavelength illuminator (e.g., red, greenand blue) at the time when each of these images was captured. Accordingto a simple setting, at a given time period, the stereoscopic imagingapparatus produces six images, three for each side, two for each color(e.g., a left side blue image, a left side green image, a left side redimage, a right side blue image, a right side green image and a rightside red image).

Alternatively, a rotating disk having an opaque portion and amulti-wavelength transparent portion, is placed in front of theperiscope assembly and an illuminator illuminates the three-dimensionalobject. As the rotating disk rotates, the periscope assembly receives asequence of right side and left side view images of thethree-dimensional object, in different ranges of wavelengths and directsthese images to the light sensor array. This embodiment is similar tothe embodiments described herein above in connection with FIGS. 14B, 20Aand 20B.

With reference to FIG. 30A, a multi-wavelength rotating disk replacesright side filter 1202 and left side filter 1204, and an illuminatorreplaces illuminating unit 1240. The multi-wavelength rotating disk isdivided to an opaque portion and to a transparent portion. Thetransparent portion is divided to substantially equal filtering sectors,each filtering sector being in a different color, as described hereinbelow in connection with FIG. 40A. Alternatively, the multi-wavelengthrotating disk is alternately divided into opaque sectors and filteringsectors, wherein each filtering sector is in a different predeterminedrange of wavelengths, as described herein below in connection with FIG.40B. The multi-wavelength rotating disk is coupled with the controller.

The illuminator provides light at least in the predetermined ranges ofwavelengths as defined by the filtering sectors. As the multi-wavelengthrotating disk rotates, the light sensor array detects a sequence ofimages. The controller determines the type of each of these images(i.e., either right side view image or left side view image) and therange of wavelengths of each of these images, according to the positionof the multi-wavelength rotating disk.

According to another aspect of the disclosed technique, a pair ofpolarizers direct an image from one side of a three-dimensional objectto an image detector, when both polarizers are oriented at the sameangle, while another pair of polarizers block an image from another sideof the object, when the polarizers are oriented 90 degrees apart. Therelative polarization angles between the two polarizers in each pair isalternately changed to be either zero or 90 degrees. Thus, the imagedetector alternately receives images from different sides of thethree-dimensional object.

Reference is now made to FIGS. 31A and 31B. FIG. 31A is a schematicillustration of a stereoscopic imaging apparatus in a right side viewimage mode, generally referenced 1300, constructed and operative inaccordance with another embodiment of the disclosed technique. FIG. 31Bis a schematic illustration of the apparatus of FIG. 30A, in a left sideview image mode.

Apparatus 1300 includes a periscope assembly 1302, a right polarizer1304, a left polarizer 1306, a main polarizer 1308, an optical assembly1310, a light sensor array 1312, a controller 1314, a storage unit 1316and an image processor 1318. Periscope assembly 1302 includes a rightmirror 1320, a left mirror 1322, a right center mirror 1324 and a leftcenter mirror 1326.

Each of right polarizer 1304, left polarizer 1306 and main polarizer1308 is an optical element which admits light only at a predetermineddirection of polarization. In the following example, the polarizationangle of the incident light beam is zero degrees, and the polarizer isrotated by 45 degrees relative to this polarization angle. The lightvector, having a length of L and being set at zero angle, can bedescribed as a vectorial combination of two vectors, each at a length√{square root over (2)}L, one directed at 45 degrees and the otherdirected at −45 degrees. The polarizer admits the vector which isdirected at 45 degrees and blocks the vector which is directed at −45degrees. The polarization angle of a polarizer can be changedelectronically. The polarization angle of right polarizer 1304 and leftpolarizer 1306 is fixed, whereas the polarization angle of mainpolarizer 1308 can be changed. In the example set forth in FIG. 31A, thepolarization angle of left polarizer 1306 is approximately 90 degreesrelative to the polarization angle of right polarizer 1304 and thepolarization angle of main polarizer 1308 is approximately the same asthat of right polarizer 1304. Thus, main polarizer 1308 admits light,which exits right polarizer 1304 and blocks light which exits leftpolarizer 1306. In the example set forth in FIG. 31B, the polarizationangle of main polarizer 1308 is approximately 90 degrees relative toright polarizer 1304. In this case, main polarizer 1308 admits lightwhich exits left polarizer 1306 and blocks light which exits rightpolarizer 1304.

With reference to FIGS. 31A and 31B, periscope assembly 1302 is locatedbetween a three-dimensional object 1328 on one side and right polarizer1304 and left polarizer 1306 on the other side. Right polarizer 1304 andleft polarizer 1306 are located side by side between periscope assembly1302 and optical assembly 1310. Main polarizer 1308 is located betweenoptical assembly 1310 and light sensor array 1312. Main polarizer 1308,light sensor array 1312, controller 1314, storage unit 1316 and imageprocessor 1318 are interconnected via a bus 1338. Controller 1314controls the polarization angle of main polarizer 1308.

In the example set forth in FIG. 31A, the polarization angle of mainpolarizer 1308 is substantially the same as that of right polarizer 1304and 90 degrees relative to left polarizer 1306. Right mirror 1320receives a right side view image of three-dimensional object 1328, vialight beams 1330 and 1332. Left mirror 1322 receives a left side viewimage of three-dimensional object 1328, via light beams 1334 and 1336.Right center mirror 1324 reflects the reflection of light beams 1330 and1332 from right mirror 1320, toward optical assembly 1310. Left centermirror 1326 reflects the reflection of light beams 1334 and 1336 fromleft mirror 1322, toward optical assembly 1310.

Optical assembly 1310 focuses light beams 1330, 1332, 1334 and 1336 onlight sensor array 1312. Since the polarization angles of rightpolarizer 1304 and left polarizer 1306 are approximately 90 degreesapart, main polarizer 1308 blocks light beams 1334 and 1336. Since thepolarization angle of main polarizer 1308 is approximately the same asthat of right polarizer 1304, main polarizer 1308 passes light beams1330 and 1332 toward light sensor array 1312. Controller 1314 enableslight sensor array 1312 to detect a right side view image ofthree-dimensional object 1328, according to the polarization angle mainpolarizer 1308. Controller 1314 stores this right side view image instorage unit 1316.

With reference to FIG. 31B, the polarization angle of main polarizer1308 is substantially the same as that of left polarizer 1306 and 90degrees relative to right polarizer 1304. In this case, main polarizer1308 blocks light beams 1330 and 1332, and passes light beams 1334 and1336 toward light sensor array 1312. Controller 1314 enables lightsensor array 1312 to detect a left side view image of three-dimensionalobject 1328, according to the polarization angle of main polarizer 1308.Controller 1314 stores this left side view image in storage unit 1316.Image processor 1318 concurrently retrieves the right side view imagesand the left side view images of three-dimensional object 1328,processes these images and provides a respective video signal to astereoscopic display, such as stereoscopic display 214 (FIG. 2).

Alternatively, a rotating polarizing disk replaces right polarizer 1304and left polarizer 1306. The rotating polarizing disk is divided to twopolarizing sections. The polarization angle of the first section issubstantially equal to the polarization angle of the main polarizer andthe polarization angle of the second section is away from thepolarization angle of the main polarizer, by substantially 90 degrees.It is noted that certain limitations may apply to such a rotatingpolarizing disk, whereas the polarizers on the disk physically rotate.Accordingly, the rotating polarizing disk may include dynamicpolarizers, which change according to the angular position of therotating polarizing disk. Alternatively, the rotating polarizing disk isstopped or slowed down at predetermined angular positions, when an imageis acquired.

It is noted that different structures of polarizers can be used forseparating the images. Such structures include active and passivepolarizers, located at various positions such as between the object andthe periscope assembly, between the periscope assembly and the opticalassembly and between the optical assembly and the light sensor array.The following are mere examples for such structures of polarizes.

Alternatively, main polarizer 1308 is located between three-dimensionalobject 1328 and periscope assembly 1302, while right polarizer 1304 andleft polarizer 1306 are located between periscope assembly 1302 andoptical assembly 1310. Further alternatively, right polarizer 1304 andleft polarizer 1306 are located between three-dimensional object 1328and periscope assembly 1302, while main polarizer 1308 is locatedbetween periscope assembly 1302 and optical assembly 1310.

Yet further alternatively, right polarizer 1304 and left polarizer 1306are located between three-dimensional object 1328 and periscope assembly1302, while main polarizer 1308 is located between optical assembly 1310and light sensor array 1312. Still further alternatively, main polarizer1308 is located between periscope assembly 1302 and optical assembly1310, while right polarizer 1304 and left polarizer 1306 are locatedbetween optical assembly 1310 and light sensor array 1312. Yet furtheralternatively, main polarizer 1308 is located between three-dimensionalobject 1328 and periscope assembly 1302, while right polarizer 1304 andleft polarizer 1306 are located between optical assembly 1310 and lightsensor array 1312.

Still further alternatively, right polarizer 1304 and left polarizer1306 are located between three-dimensional object 1328 and mainpolarizer 1308. Main polarizer 1308 is located between right polarizer1304 and left polarizer 1306 on one side and periscope assembly 1302 onthe other side.

Yet further alternatively, main polarizer 1308 is located betweenthree-dimensional object 1328 on one side and right polarizer 1304 andleft polarizer 1306 on the other side. Right polarizer 1304 and leftpolarizer 1306 are located between main polarizer 1308 and periscopeassembly 1302.

Still further alternatively, right polarizer 1304 and left polarizer1306 are located between periscope assembly 1302 and main polarizer1308. Main polarizer 1308 is located between right polarizer 1304 andleft polarizer 1306 on one side and optical assembly 1310 on the otherside.

Yet further alternatively, main polarizer 1308 is located betweenperiscope assembly 1302 on one side and right polarizer 1304 and leftpolarizer 1306 on the other side. Right polarizer 1304 and leftpolarizer 1306 are located between main polarizer 1308 and opticalassembly 1310.

Still further alternatively, right polarizer 1304 and left polarizer1306 are located between optical assembly 1310 and main polarizer 1308.Main polarizer 1308 is located between right polarizer 1304 and leftpolarizer 1306 on one side and light sensor array 1312 on the otherside.

Yet further alternatively, main polarizer 1308 is located betweenoptical assembly 1310 on one side and right polarizer 1304 and leftpolarizer 1306 on the other side. Right polarizer 1304 and leftpolarizer 1306 are located between main polarizer 1308 and light sensorarray 1312.

Further alternatively, the polarization angle of main polarizer 1308 isfixed and the polarization angle of right polarizer 1304 and leftpolarizer 1306 can be changed. In this case, controller 1314 is coupledwith right polarizer 1304 and left polarizer 1306 instead of mainpolarizer 1308 and hence, controller 1314 controls the angle of bothright polarizer 1304 and left polarizer 1306. The polarization angles ofright polarizer 1304 and left polarizer 1306 are changed substantiallysimultaneously and alternately by substantially 90 degrees each time,while the angle there between is substantially 90 degrees at all times.

According to another aspect of the disclosed technique, the imagedifferentiator includes a combination of polarizers and polarizationrotating cells. Each polarization rotating cell sequentially changes thepolarization angle of light which exits each of two polarizers.

According to one embodiment, the image differentiator includes a frontright polarizer, a front left polarizer, a polarization rotating celland a main polarizer. The front right polarizer and the front leftpolarizer are located in the right channel and the left channel,respectively. The polarization rotating cell is located in the commonpath. The main polarizer is located in the common path between thepolarization rotating cell and the light sensor array. The polarizationangle of the front right polarizer is substantially equal to thepolarization angle of the main polarizer, while the polarization angleof the front left polarizer is approximately 90 degrees away from thatof the main polarizer. The polarization rotating cell receives lightfrom both the front right polarizer and the front left polarizer. Thepolarization rotating cell is coupled with the controller.

A polarization rotating cell is generally in form of a crystal whichchanges the polarization angle of the incoming light by a selectedvalue. In the present example, the polarization rotating cell alternatesbetween two states. At the first state, the polarization rotating cellrotates any light incident thereon by a zero angle, thereby leaving thepolarization angle of that incident light, unchanged. At the secondstate, the polarization rotating cell rotates any light incidentthereon, by a substantially right angle (i.e., 90 degrees).

When the polarization rotating cell is in the first state, thepolarization rotating cell leaves the polarization of the light exitingthe front right polarizer and the front left polarizer unchanged. Sincethe polarization of the front right polarizer is substantially equal tothe polarization of the main polarizer, the main polarizer admits thelight which previously exited the front right polarizer. Since thepolarization of the front left polarizer is substantially rotated at 90degrees away from the polarization of the main polarizer, the mainpolarizer blocks the light which previously exited the front leftpolarizer. Thus, the main polarizer admits the right side view image ofthe three-dimensional object to the light sensor array, while the mainpolarizer blocks the left side view image of the three-dimensionalobject.

When the polarization rotating cell is in the second state, thepolarization rotating cell rotates the polarization of the lightreceived from the front right polarizer and from the front leftpolarizer, by substantially 90 degrees. In this case, the polarizationof the light which previously exited the front left polarizer, isrotated to be substantially equal to the polarization angle of the mainpolarizer. Furthermore, the polarization of the light which exited thefront right polarizer is rotated to be at substantially 90 degrees awayfrom the polarization of the main polarizer. The main polarizer admitsthe light which previously exited the front left polarizer, while themain polarizer blocks the light which previously exited the front rightpolarizer. Thus, the main polarizer admits the left side view image ofthe three-dimensional object to the light sensor array, while the mainpolarizer blocks the right side view image of the three-dimensionalobject. The controller enables the light sensor array to detect theright side view image and the left side view image of thethree-dimensional object, according to the rotating state of thepolarization rotating cell.

According to another embodiment, a right polarization rotating cell islocated between the front right polarizer and the main polarizer, in theright channel and a left polarization rotating cell is located betweenthe front left polarizer and the main polarizer, in the left channel.The main polarizer is located in the common path, between the rightpolarization rotating cell and the left polarization rotating cell onone side and the light sensor array on the other. The front rightpolarizer, the front left polarizer and the main polarizer are staticpolarizers. The polarization angles of the front right polarizer, thefront left polarizer and the main polarizer are substantially equal. Theright polarization rotating cell and the left polarization rotating cellare coupled with the controller, which alternately provides two statesof operation.

In the first state of operation, the controller sets the rotation angleof the right polarization rotating cell to zero degrees and the rotationangle of the left polarization rotating cell to 90 degrees. Accordingly,the polarization of the light which previously exited the front rightpolarizer remains substantially unchanged, while the polarization of thelight which previously exited the front left polarizer is changed by asubstantially right angle. The main polarizer admits the light whichpreviously exited the front right polarizer, while the main polarizerblocks the light previously exited the front left polarizer. Thus, themain polarizer admits the right side view image of the three-dimensionalobject to the light sensor array, while blocking the left side viewimage of the three-dimensional object.

In the second state of operation, the controller sets the rotation angleof the left polarization rotating cell to zero degrees and the rotationangle of the right polarization rotating cell to 90 degrees.Accordingly, the polarization of the light which previously exited thefront left polarizer remains substantially unchanged, while thepolarization of the light which previously exited the front rightpolarizer is changed by substantially 90 degrees. The main polarizeradmits the light which previously exited the front left polarizer, whilethe main polarizer blocks the light previously exited the front rightpolarizer. Thus, the main polarizer admits the left side view image ofthe three-dimensional object to the light sensor array, while the mainpolarizer blocks the right side view image of the three-dimensionalobject. The controller enables the light sensor array to detect theright side view image and the left side view image of thethree-dimensional object, according to the rotating states of the rightpolarization rotating cell and the left polarization rotating cell.

According to another embodiment, the main polarizer is eliminated, thefront right polarizer and the front left polarizer are static polarizersand the polarization angle of the front right polarizer is substantially90 degrees away from the polarization angle of the front left polarizer.In addition a polarized light source is employed, which is coupled withthe controller. The polarized light source alternately illuminates thethree-dimensional object with light at a first polarization angle and ata second polarization angle. The first polarization angle of theilluminating light is substantially equal to the polarization angle ofthe front right polarizer and the second polarization angle of theilluminating light is substantially equal to the polarization angle ofthe front left polarizer.

When the polarized light source illuminates the three-dimensional objectat the polarization angle of the front right polarizer, the periscopeassembly directs the right side view image of the three-dimensionalobject to the front right polarizer, substantially at the polarizationangle of the front right polarizer. Simultaneously, the periscopeassembly directs the left side view image of the three-dimensionalobject to the front left polarizer, substantially at the polarizationangle of the front right polarizer. Since the polarization angle of theright side view image is substantially equal to the polarization angleof the front right polarizer, the front right polarizer admits the rightside view image of the three-dimensional object to the light sensorarray, through the optical assembly. Since the polarization angle of theleft side view image is substantially 90 degrees away from thepolarization angle of the front left polarizer, the front left polarizerblocks the left side view image of the three-dimensional object.

When the polarized light source illuminates the three-dimensional objectat the polarization angle of the front left polarizer, the periscopeassembly directs the left side view image of the three-dimensionalobject to the front left polarizer, substantially at the polarizationangle of the front left polarizer. Simultaneously, the periscopeassembly directs the right side view image of the three-dimensionalobject to the front right polarizer, substantially at the polarizationangle of the front left polarizer. Since the polarization angle of theleft side view image is substantially equal to the polarization angle ofthe front left polarizer, the front left polarizer admits the left sideview image of the three-dimensional object to the light sensor array,through the optical assembly. Since the polarization angle of the rightside view image is substantially 90 degrees away from the polarizationangle of the front right polarizer, the front right polarizer blocks theleft side view image of the three-dimensional object. The controllerenables the light sensor array to detect the right side view image andthe left side view image of the three-dimensional object, according tothe illuminating state of the polarized light source.

It is noted that in this case, the three-dimensional object isilluminated only with light at a selected polarization angle at eachstate of the polarized light source. Thus, the three-dimensional objectis heated substantially less and the physical properties thereof remainsubstantially stable.

Reference is now made to FIG. 32, which is a schematic illustration of amethod for operating a stereoscopic imaging apparatus, operative inaccordance with another embodiment of the disclosed technique. In step1400, two images are received from different sides of an object, throughtwo spaced apart apertures. With reference to FIG. 28A, periscopeassembly 1102 receives a right side view image and a left side viewimage of three-dimensional object 1118.

In step 1402, the two received images are directed to a common path.With reference to FIG. 28A, periscope assembly 1102 directs the rightside view image as light beams 1120C and 1122C, and the left side viewimage as light beams 1124C and 1126C, through optical assembly 1104, tolenticular lens layer 1106.

In step 1404, the two received images are differentiated. With referenceto FIG. 28A, lenticular lens layer 1106 differentiates between the rightside view image and the left side view image of three-dimensional object1118, and directs each differentiated image to light sensor array 1108.Light sensor array 1108, then detects the differentiated images (step1406).

According to another embodiment of the disclosed technique, theperiscope assembly moves between a retracted position and an extendedposition. Thus, the endoscope is entered into the body of the patientwhile the periscope assembly is retracted, thereby assuming a narrowshape, capable of entering through narrow passages. When the endoscopeis located in a selected region within the body of the patient, theperiscope assembly moves to an extended position, thereby separatingapart the apertures which receive a right side view and a left side viewof the selected region. The periscope, then transfers substantiallydistinct right side view and left side view images of the selectedregion, to an image detector via an optical assembly.

Reference is now made to FIGS. 33A and 33B. FIG. 33A is a schematicillustration of an endoscope with a periscope assembly thereof in aretracted mode, generally referenced 1450, constructed and operative inaccordance with a further embodiment of the disclosed technique. FIG.33B is a schematic illustration of the periscope of the endoscope ofFIG. 33A, in an extended mode.

Endoscope 1450 includes a periscope assembly 1452, an optical assembly1454, a lenticular lens layer 1456, and a light sensor array 1458.Periscope assembly 1452 includes a right mirror 1460, a left mirror1462, a right center mirror 1464, a left center mirror 1466, and hinges1468, 1470 and 1472. Optical assembly 1454 includes a plurality oflenses 1474 and 1476.

Periscope assembly 1452 is located at a distal end 1478 of endoscope1450. Optical assembly 1454 is located between periscope assembly 1452and lenticular lens array 1456. Lenticular lens array 1456 is locatedbetween optical assembly 1454 and light sensor array 1458. Right mirror1460 and left mirror 1462 can rotate about hinges 1468 and 1470,respectively. Right center mirror 1464 and left center mirror 1466 canrotate about hinge 1472.

With reference to FIG. 33B, right mirror 1460 and left center mirror1466 rotate clockwise about hinges 1468 and 1472, respectively. Leftmirror 1462 and right center mirror 1464 rotate counterclockwise abouthinges 1470 and 1472, respectively. Thus, periscope assembly 1452 movesto an extended position. Right mirror 1460 and left mirror 1462 receivea right side view and a left side view, respectively, of athree-dimensional object 1480. Right center mirror 1464 and left centermirror 1466 reflect a right side view image and a left side view imageof three-dimensional object 1480, as reflected from right mirror 1460and left mirror 1462, respectively, to optical assembly 1454. Opticalassembly 1454 focuses the right side view image and the left side viewimage of three-dimensional object 1480, on lenticular lens layer 1456.Lenticular lens layer 1456 differentiates between the right side viewimage and the left side view image, and the respective detectionelements of light sensor array 1458 detect the right side view image andthe left side view image of three-dimensional object 1480.

Reference is now made to FIGS. 34A and 34B. FIG. 34A is a schematicillustration of an endoscope with a periscope assembly thereof in aretracted mode, generally referenced 1500, constructed and operative inaccordance with another embodiment of the disclosed technique. FIG. 34Bis a schematic illustration of the periscope assembly of the endoscopeof FIG. 34A, in an extended mode.

Endoscope 1500 includes a periscope assembly 1502, an optical assembly1504, a lenticular lens layer 1506, and a light sensor array 1508.Periscope assembly 1502 includes a right prism 1510, a left prism 1512,a hinge 1514, a rail 1516 and a stop 1518. Optical assembly 1504includes a plurality of lenses 1520 and 1522. Each of right prism 1510and left prism 1512 is a prism whose longitudinal cross section is aparallelogram. Right prism 1510 and left prism 1512 can rotate abouthinge 1514. Hinge 1514 can slide within rail 1516 in directionsdesignated by arrows 1524 and 1526. Stop 1518 is coupled with rail 1516.Periscope assembly 1502 is located at a distal end 1528 of endoscope1500. Optical assembly 1504 is located between periscope assembly 1502and lenticular lens layer 1506. Lenticular lens layer 1506 is locatedbetween optical assembly 1504 and light sensor array 1508.

With reference to FIG. 34B, hinge 1514 slides within rail 1516 indirection 1524, surfaces 1530 and 1532 of right prism 1510 and leftprism 1512, respectively, make contact with stop 1518 and thus, rightprism 1510 and left prism 1512 move to an extended position. In thisposition, reflective surfaces 1534 and 1536 of right prism 1510 and leftprism 1512, respectively, located distal to hinge 1514, receive a rightside view image and a left side view image of a three-dimensional object1538. Reflective surface 1540 and 1542 of right prism 1510 and leftprism 1512, respectively, located proximal to hinge 1514, reflect theright side view image and the left side view image, as reflected fromreflective surfaces 1534 and 1536, respectively, to optical assembly1504.

Optical assembly 1504 focuses the right side view image and the leftside view image of three-dimensional object 1538, on lenticular lenslayer 1506. Lenticular lens layer 1506 differentiates between the rightside view image and the left side view image, and the respectivedetection elements of light sensor array 1508 detect the right side viewimage and the left side view image of three-dimensional object 1538.When hinge 1514 moves in direction 1526, surfaces 1530 and 1532 makecontact with stop 1518 and right prism 1510 and left prism 1512 moveback to the retracted position of FIG. 34A. It is noted that instead oflenticular lens layer 1506, other types of image differentiators can beemployed, such as a pair of filters, a multi-wavelength rotating disk, apartially-transparent rotating disk, a pair of polarizers, a multipleaperture, and the like.

Reference is now made to FIGS. 35A and 35B. FIG. 35A is a schematicillustration of a stereoscopic imaging apparatus, generally referenced1560, constructed and operative in accordance with a further embodimentof the disclosed technique. FIG. 35B is a schematic illustration of theapparatus of FIG. 35A, in which the periscope assembly thereof is in adifferent mode than that of FIG. 35A.

Apparatus 1560 includes a periscope assembly 1562, an optical assembly1564, a light sensor array 1566, a controller 1568, a storage unit 1570and an image processor 1572. Periscope assembly 1562 includes a rightmirror 1574, a left mirror 1576, a rotating mirror 1578 and a hinge1580. One side of rotating mirror 1578 is reflective and the other sidethereof is non-reflective. Periscope assembly 1562 is located between athree-dimensional object 1582 and optical assembly 1564. Opticalassembly 1564 is located between periscope assembly 1562 and lightsensor array 1566. Hinge 1580 is coupled with a moving element (notshown), such as a piezoelectric element, a pulling force of a cableagainst a spring, and the like. The moving element, light sensor array1566, storage unit 1570 and image processor 1572 are interconnected viaa bus 1592.

Right mirror 1574 is oriented at a slanted angle with respect tothree-dimensional object 1582 and at the right side of three-dimensionalobject 1582, such that right mirror 1574 receives a right side viewimage of three-dimensional object 1582. This slanted angle is preferablyclose to 45 degrees. Left mirror 1576 is oriented at another slantedangle, opposite to the slanted angle of right mirror 1574 and at theleft side of three-dimensional object 1582. Left mirror 1576 receives aleft side view image of three-dimensional object 1582.

The moving element alternately rotates rotating mirror 1578 about hinge1580, between two positions. At one position, rotating mirror 1578 isoriented at an angle substantially parallel to the slanted angle ofright mirror 1574. In this position, the reflective side of rotatingmirror 1578 faces right mirror 1574 while the non-reflective side ofrotating mirror 1578 faces left mirror 1576. At another position,rotating mirror 1578 is oriented at an angle substantially parallel tothe slanted angle of left mirror 1576. In this position, the reflectiveside of rotating mirror 1578 faces left mirror 1576 while thenon-reflective side of rotating mirror 1578 faces right mirror 1574.

With reference to FIG. 35A, rotating mirror 1578 is oriented at an anglesubstantially parallel to right mirror 1574 and approximately at 90degrees relative to the orientation of left mirror 1576, such that thereflective side of rotating mirror 1578 faces right mirror 1574. Rightmirror 1574 receives light beams 1584 and 1586, which includeinformation respective of the right side view image of three-dimensionalobject 1582. Rotating mirror 1578 reflects light beams 1584 and 1586, asreflected by right mirror 1574, to optical assembly 1564. Opticalassembly 1564 focuses light beams 1584 and 1586 on light sensor array1566. Controller 1568 enables light sensor array 1566 to detect a rightside view image of three-dimensional object 1582, according to theposition of rotating mirror 1578. Controller 1568 stores this right sideview image in storage unit 1570.

Left mirror 1576 receives light beams 1588 and 1590, which includeinformation respective of the left side view image of three-dimensionalobject 1582. Since the non-reflective side of rotating mirror 1578 isfacing left mirror 1576, this non-reflective side absorbs light beams1588 and 1590. Thus, light beams 1588 and 1590 reach neither opticalassembly 1564 nor light sensor array 1566, nor is reflected or refractedlight incident upon the three-dimensional object 1582, and light sensorarray 1566 does not detect the left side view image of three-dimensionalobject 1582.

With reference to FIG. 35B, rotating mirror 1578 rotates 90 degreescounterclockwise relative to the position illustrated in FIG. 35A. Inthe position illustrated in FIG. 35B, rotating mirror 1578 is orientedat an angle substantially parallel to left mirror 1576 and approximatelyat 90 degrees relative to the orientation of right mirror 1574. Thereflective side of rotating mirror 1578 faces left mirror 1576 and thenon-reflective side thereof faces right mirror 1574. Rotating mirror1578 reflects light beams 1588 and 1590, as reflected by left mirror1576, to optical assembly 1564. Optical assembly 1564 focuses lightbeams 1588 and 1590 on light sensor array 1566. Controller 1568 enableslight sensor array 1566 to detect a left side view image ofthree-dimensional object 1582, according to the position of rotatingmirror 1578. Controller 1568 stores this left side view image in storageunit 1570.

Since the non-reflective side of rotating mirror 1578 faces right mirror1574, this non-reflective side absorbs light beams 1584 and 1586. Thus,light beams 1584 and 1586 reach neither optical assembly 1564 nor lightsensor array 1566, nor is reflected or refracted light incident upon thethree-dimensional object 1582, and light sensor array 1566 does notdetect the right side view image of three-dimensional object 1582.Rotating mirror 1578, then rotates 90 degrees clockwise to the positionillustrated in FIG. 35A and provides another right side view image ofthree-dimensional object 1582 to light sensor array 1566. Imageprocessor 1572 produces a video signal for a stereoscopic display, suchas stereoscopic display 214 (FIG. 2), by retrieving the right side andleft side view images from storage unit 1570 and processing them.

Alternatively, an optical element, such as an optical diaphragm, prism,mirror and the like, replaces rotating mirror 1578. Half of the opticaldiaphragm is transparent and the other half is opaque. The opticaldiaphragm oscillates about an axis, by an electronic element, such aspiezoelectric element, and the like, such that the transparent and theopaque portions of the diaphragm are alternately located above rightmirror 1574 and left mirror 1576.

According to another aspect of the disclosed technique, two fiberscopesare employed whose inlets are substantially spaced apart relative to theoutlets thereof. One fiberscope obtains a right side view image of thethree-dimensional object, while the other fiberscope obtains a left sideview image of the three-dimensional object.

Reference is now made to FIG. 36, which is a schematic illustration of astereoscopic imaging apparatus, generally referenced 1620, constructedand operative in accordance with another embodiment of the disclosedtechnique. Apparatus 1620 includes inlet lenses 1666 and 1668, a lightdirecting assembly 1622, outlet lenses 1670 and 1672, a multipleaperture 1624, an optical assembly 1626, a light sensor array 1628, acontroller 1630, a storage unit 1632 and an image processor 1634. Lightdirecting assembly 1622 includes a right fiberscope 1636 and a leftfiberscope 1638.

A fiberscope is a flexible longitudinal element, which is generallyemployed for obtaining an image of an object which is obstructed byother objects and can not be viewed directly. The fiberscope includes asubstantially large number of fibers. One end of each fiber receives theimage of a substantially small portion of the object at the inlet of thefiberscope and conveys this image to the other end of the same fiber, atthe outlet of the fiberscope. Thus, the plurality of the fibers,together provide a complete image of the object at the outlet of thefiberscope, duplicating the image detected by the fiberscope at theinlet thereof.

The relative positions of the ends of the fibers at the outlet of thefiberscope, are the same as the relative positions of the fibers at theinlet of the fiberscope (i.e., substantially no twist of the fibersalong the length of the fiberscope is allowed). Otherwise, the image ofthe object at the outlet of the fiberscope will be skewed and differentfrom the image of the object as viewed by the inlet of the fiberscope.

Right fiberscope 1636 includes an image inlet 1640, an image outlet 1642and a plurality of fibers 1644. Left fiberscope 1638 includes an imageinlet 1646, an image outlet 1648 and a plurality of fibers 1650.Multiple aperture 1624 includes a right aperture 1652 _(R) and a leftaperture 1652 _(L). Multiple aperture 1624 is similar to multipleaperture 804, as described herein above in connection with FIG. 20A.Multiple aperture 1624, light sensor array 1628, controller 1630,storage unit 1632 and image processor 1634 are interconnected via a bus1674. Controller 1630 controls the alternate closure and opening ofright aperture 1652 _(R) and left aperture 1652 _(L).

Light directing assembly 1622 is located between a three-dimensionalobject 1654 and multiple aperture 1624. Multiple aperture 1624 islocated between light directing assembly 1622 and optical assembly 1626.Optical assembly 1626 is located between multiple aperture 1624 andlight sensor array 1628. Inlet lenses 1666 and 1668 are located betweenthree-dimensional object 1654 and image inlets 1640 and 1646,respectively. Outlet lenses 1670 and 1672 are located between multipleaperture 1624 and image outlets 1642 and 1648, respectively.

Right fiberscope 1636 and left fiberscope 1638 are bent, such that imageinlets 1640 and 1646 are spaced apart and image inlets 1642 and 1648 arelocated close together. In this manner, right fiberscope 1636 obtains animage of three-dimensional object 1654 from the right side thereof,which is substantially different from another image obtained by leftfiberscope 1638, from the left side of three-dimensional object 1654.

Light beams 1658 and 1660 include information respective of the rightside view image of three-dimensional object 1654. Inlet lens 1666focuses light beams 1658 and 1660 on image inlet 1640. Fibers 1644convey light beams 1658 and 1660 to image outlet 1642. Outlet lens 1670focuses light beams 1658 and 1660 on right aperture 1652 _(R). Sinceright aperture 1652 _(R) is open, light beams 1658 and 1660 reachoptical assembly 1626 _(R), optical assembly 1626 _(R) focuses lightbeams 1658 and 1660 on light sensor array 1628. Controller 1630 enableslight sensor array 1628 to detect a right side view image ofthree-dimensional object 1654, according to the state of multipleaperture 1624 (i.e., when right aperture 1652 _(R) is open). Controller1630 stores this right side view image in storage unit 1632.

Light beams 1662 and 1664 include information respective of the leftside view image of three-dimensional object 1654. Inlet lens 1668focuses light beams 1662 and 1664 on image inlet 1646. Fibers 1650convey light beams 1662 and 1664 to image outlet 1648. Outlet lens 1672focuses light beams 1662 and 1664 on left aperture 1652 _(L). Since leftaperture 1652 _(L) is closed, light beams 1662 and 1664 are blocked andlight sensor array 1628 does not detect the left side view image ofthree-dimensional object 1654.

In another mode of apparatus 1620 (not shown), right aperture 1652 _(R)is closed and left aperture 1652 _(L) is open. Thus, left aperture 1652_(L) allows light beams 1662 and 1664 to pass there through and reachoptical assembly 1626. Optical assembly 1626 focuses light beams 1662and 1664 on light sensor array 1628. Controller 1630 enables lightsensor array 1628 to detect a left side view image of three-dimensionalobject 1654, according to the state of multiple aperture 1624 (i.e.,when left aperture 1652 _(L) is open). Controller 1630 stores this leftside view image in storage unit 1632. Image processor 1634 produces avideo signal for a stereoscopic display, such as stereoscopic display214 (FIG. 2), by retrieving these images from storage unit 1632 andprocessing them.

According to another aspect of the disclosed technique, a plurality ofan arm of Y-junction fibers are spaced from a plurality of another armof the Y-junction fibers. The plurality of each arm of the Y-junctionfibers alternately transfer an image of a three-dimensional object, asviewed from the respective side, to the plurality of the legs of theY-junction fibers.

Reference is now made to FIGS. 37A and 37B. FIG. 37A is a schematicillustration of a stereoscopic imaging apparatus, generally referenced1700, constructed and operative in accordance with a further embodimentof the disclosed technique. FIG. 37B is a schematic illustration of asplit fiber of the light directing assembly of the apparatus of FIG.37A.

Apparatus 1700 includes an image differentiator 1702, a right lens 1748,a left lens 1750, a light directing assembly 1704, an optical assembly1706 and a light sensor array 1708. Image differentiator 1702 caninclude a right side filter 1710 and a left side filter 1712, similar toright side filter 1202 and left side filter 1204, respectively, asdescribed herein above in connection with FIG. 30A. Alternatively, imagedifferentiator 1702 is a multiple aperture such as multiple aperture1154 (FIG. 29A).

If image differentiator 1702 is a filter type image differentiator, thenimage differentiator 1702 includes right side filter 1710 and left sidefilter 1712. In this case, apparatus 1700 further includes twoilluminators (not shown) similar to illuminators 1212 and 1214 asdescribed herein above in connection with FIG. 30A. The two illuminatorsare coupled with a controller, such as controller 1216 (FIG. 30A). Inthe foregoing discussion, image differentiator 1702 is a filter typedifferentiator.

Light directing assembly 1704 includes a sleeve 1714, a right inlet1716, a left inlet 1718, an outlet 1720 and a plurality of split fibers1722. Sleeve 1714 includes a right section 1724, a left section 1726 anda common section 1728.

Image differentiator 1702 is located between a three-dimensional object1730, and right lens 1748 and left lens 1750. Right lens 1748 is locatedin front of right inlet 1716 and it produces a right side view image ofthree-dimensional object 1730 on right inlet 1716. Left lens 1750 islocated in front of left inlet 1718 and it produces a left side viewimage of three-dimensional object 1730 on left inlet 1718. Lightdirecting assembly 1704 is located between right lens 1748 and left lens1750, on the one side, and optical assembly 1706, on the other side.Optical assembly 1706 is located between light directing assembly 1704and light sensor array 1708.

With reference to FIG. 37B, split fiber 1722 is in the form of aY-junction. Split fiber 1722 includes a right arm 1732, a left arm 1734and a common arm 1736. Right arm 1732 and left arm 1734 merge intocommon arm 1736, such that light can enter common arm 1736 through bothright arm 1732 and left arm 1734. Sleeve 1714 is constructed in the formof a Y-junction, such that right inlet 1716 and left inlet 1718 arelocated at the right and left apex of the letter “Y”, respectively, andoutlet 1720 is located on the leg of the letter “Y”. Split fibers 1722are arranged within sleeve 1714, such that right arm 1732 of each splitfiber 1722 is located in right section 1724 of sleeve 1714 and left arm1734 of the respective split fiber 1722 is located in left section 1726of sleeve 1714. Common arm 1736 of all split fibers 1722 are located incommon section 1728 of sleeve 1714.

Right inlet 1716 can receive a right side view image ofthree-dimensional object 1730 and left inlet 1718 can receive a leftside view image thereof. The controller controls the operation of imagedifferentiator 1702 and the two illuminators, such that right inlet 1716and left inlet 1718 alternately receive the right side view image andthe left side view image, respectively, of three-dimensional object1730.

Each of a plurality of the right arms 1732 receives a substantiallysmall portion of the right side view image of three-dimensional object1730 and transfers this portion of the image to the respective commonarm 1736. The plurality of the common arms 1736, together produce thecomplete right side view image of three-dimensional object 1730, asreceived by the plurality of the right arms 1732. In the same manner, aplurality of left arms 1734 transfers the left side view image ofthree-dimensional object 1730, to the plurality of common arms 1736. Thecommon arms 1736 together produce the complete left side view image ofthree-dimensional object 1730, as received by the plurality of the leftarms 1734.

The relative positions of common arms 1736 of split fibers 1722 withincommon section 1728, are substantially the same as the relativepositions of right arms 1732 within right section 1724, and the relativepositions of left arms 1734 within left section 1726. Otherwise, theimage of three-dimensional object 1730 at outlet 1720 will be skewed anddifferent from the image of three-dimensional object 1730 as viewed byeither right inlet 1716 or left inlet 1718.

If the split fibers 1722 are placed within sleeve 1714, such thatjunctions 1742 (FIG. 37B) of all the split fibers 1722 are located sideby side, a substantially large space will be consumed. To mitigate thisproblem, the split fibers 1722 are placed within sleeve 1714, such thatjunctions 1742 of each split fibers 1722 are periodically andsequentially located on the top of each other, at different heights.

In the example set forth in FIG. 37A, right side filter 1710 lets thelight through. Therefore, right inlet 1716 receives light beams 1738 and1740, which include information respective of the right side view imageof three-dimensional object 1730, through right side filter 1710. Rightlens 1748 focuses light beams 1738 and 1740 on right inlet 1716, whereinright lens 1748 images the points on three-dimensional object 1730 fromwhich light beams 1738 and 1740 have arrived, on right inlet 1716. Theplurality of right arms 1732 transfer light beams 1738 and 1740 tooutlet 1720, via the respective plurality of common arms 1736. Opticalassembly 1706 receives light beams 1738 and 1740 from outlet 1720 andoptical assembly 1706 focuses light beams 1738 and 1740 on light sensorarray 1708. A processor, such as processor 208 (FIG. 2), enables lightsensor array 1708 to detect a right side view image of three-dimensionalobject 1730, according to the state of image differentiator 1702 (i.e.,when right side filter 1710 is open).

Light beams 1744 and 1746, which include information respective of theleft side view image of three-dimensional object 1730, reach left sidefilter 1712. Since left side filter 1712 is not operative, light beams1744 and 1746 are blocked and do not reach light sensor array 1708.

In another mode of apparatus 1700 (not shown), right side filter 1710blocks light beams 1738 and 1740, while left side filter 1712 letsthrough the light beams 1744 and 1746. Left lens 1750 focuses lightbeams 1744 and 1746 on left inlet 1718, wherein left lens 1750 imagesthe points on three-dimensional object 1730 from which light beams 1744and 1746 have arrived, on left inlet 1718. In this case, the pluralityof left arms 1734 transfer light beams 1744 and 1746 to outlet 1720, viathe respective plurality of common arms 1736. Optical assembly 1706receives light beams 1744 and 1746 from outlet 1720 and optical assembly1706 focuses light beams 1744 and 1746 on light sensor array 1708. Theprocessor enables light sensor array 1708 to detect a left side viewimage of three-dimensional object 1730, according to the state of imagedifferentiator 1702 (i.e., when left side filter 1712 is open).

Reference is now made to FIGS. 38A and 38B. FIG. 38A is a schematicillustration of a stereoscopic imaging apparatus, generally referenced1800, constructed and operative in accordance with another embodiment ofthe disclosed technique. FIG. 38B is a schematic illustration of theapparatus of FIG. 38A, in another mode of operation.

Apparatus 1800 includes a right side filter 1802, a left side filter1804, a periscope assembly 1806, an optical assembly 1808, a duo-tonerotating disk 1810, a light sensor array 1812, an illuminator 1814, acontroller 1816, a storage unit 1818 and an image processor 1820. Rightside filter 1802 is a light filter, which admits light in only apredetermined range of wavelengths. Left side filter 1804 is a lightfilter which admits light in another predetermined range of wavelengths,different than the range of wavelengths which is set for right sidefilter 1802. Periscope assembly 1806 is similar to periscope assembly1206, as described herein above in connection with FIG. 30A. Duo-tonerotating disk 1810 includes two filtering portions 1822 and 1824.Filtering portion 1822 admits light in a range of wavelengths whichmatches the range of wavelengths of right side filter 1802 and filteringportion 1824 admits light in another range of wavelengths which matchesthe range of wavelengths of left side filter 1804.

Illuminator 1814 provides light in at least the range of wavelengthsdefined by filtering portions 1822 and 1824. In the example set forth inFIGS. 38A and 38B, right side filter 1802 admits only red light, whereasleft side filter 1804 admits only blue light. Hence, filtering portion1822 is red (i.e., admits only red light radiation), and filteringportion 1824 is blue (i.e., admits only blue light radiation). Lightsensor array 1812 detects light in at least the range of wavelengthsdefined by filtering portions 1822 and 1824.

Right side filter 1802 and left side filter 1804 are located between athree-dimensional object 1826 and periscope assembly 1806. Periscopeassembly 1806 is located between right side filter 1802 and left sidefilter 1804, and optical assembly 1808. Optical assembly 1808 is locatedbetween periscope assembly 1806 and duo-tone rotating disk 1810.Duo-tone rotating disk 1810 is located between optical assembly 1808 andlight sensor array 1812. Duo-tone rotating disk 1810, light sensor array1812, controller 1816, storage unit 1818 and image processor 1820 areinterconnected via a bus 1848.

With reference to FIG. 38A, right side filter 1802 receives light beams1828 and 1830, which include information respective of the right sideview image of three-dimensional object 1826. Right side filter 1802directs light beams 1828 and 1830 to periscope assembly 1806, as lightbeams 1832 and 1834, respectively, which have a red tone. Left sidefilter 1804 receives light beams 1836 and 1838, which includeinformation respective of the left side view image of three-dimensionalobject 1826. Left side filter 1804 directs light beams 1836 and 1838 toperiscope assembly 1806, as light beams 1840 and 1842, respectively,which have a blue tone. Periscope assembly 1806 directs light beams1832, 1834, 1840 and 1842 to optical assembly 1808.

Optical assembly 1808 receives light beams 1832, 1834, 1840 and 1842 atinlets thereof (not shown), and directs light beams 1832, 1834, 1840 and1842 from an outlet thereof (not shown) to duo-tone rotating disk 1810.In the example set forth in FIG. 38A, duo-tone rotating disk 1810 isshown in an instant during the rotation thereof, such that filteringportion 1822 (red) is located above light sensor array 1812. Filteringportion 1822 admits only red beams of light. Thus, filtering portion1822 admits light beams 1832 and 1834, which include informationrespective of the right side view image of three-dimensional object1826. It is noted that filtering portion 1822 blocks light beams 1840and 1842 which include information respective of the left side viewimage of three-dimensional object 1826.

Controller 1816 enables light sensor array 1812 to detect a right sideview image of three-dimensional object 1826, according to the positionof duo-tone rotating disk 1810 relative to light sensor array 1812(i.e., when filtering portion 1822 is located above light sensor array1812). Controller 1816 stores this right side view image in storage unit1818.

With reference to FIG. 38B, duo-tone rotating disk 1810 is in an instantduring the rotation thereof, such that filtering portion 1824 (blue) islocated above light sensor array 1812. Filtering portion 1824 admitsonly blue beams of light. Thus, filtering portion 1824 admits lightbeams 1840 and 1842, which include information respective of the leftside view image of three-dimensional object 1826. It is noted thatfiltering portion 1824 blocks light beams 1832 and 1834 which includeinformation respective of the right side view image of three-dimensionalobject 1826. Controller 1816 enables light sensor array 1812 to detect aleft side view image of three-dimensional object 1826, according to theposition of duo-tone rotating disk 1810 relative to light sensor array1812 (i.e., when filtering portion 1824 is located above light sensorarray 1812). Controller 1816 stores this left side view image in storageunit 1818. Image processor 1820 produces a video signal for astereoscopic display, such as stereoscopic display 214 (FIG. 2), byretrieving these images from storage unit 1818 and processing them.

Reference is now made to FIGS. 39A and 39B. FIG. 39A is a schematicillustration of a partially-transparent rotating disk, generallyreferenced 1900, constructed and operative in accordance with a furtherembodiment of the disclosed technique. FIG. 39B is a schematicillustration of a partially-transparent rotating disk, generallyreferenced 1910, constructed and operative in accordance with anotherembodiment of the disclosed technique.

With reference to FIG. 39A, partially-transparent rotating disk 1900 ismade of plastic, glass, and the like. Partially-transparent rotatingdisk 1900 is divided into a transparent portion 1902 and an opaqueportion 1904. Transparent portion 1902 and opaque portion 1904 aredivided by a diameter 1906 of partially-transparent rotating disk 1900.Transparent portion 1902 admits light of a selected range of wavelength(either in the visible range or the invisible range), while opaqueportion 1904 blocks light at this selected range of wavelength.

With reference to FIG. 39B, partially-transparent rotating disk 1910includes a transparent portion 1912 and an opaque portion 1914.Transparent portion 1912 occupies one quadrant of partially-transparentrotating disk 1910, while opaque portion 1914 occupies the rest. Theproperties of transparent portion 1912 and opaque portion 1914 aresimilar to properties of transparent portion 1902 and opaque portion1904, respectively.

Reference is now made to FIGS. 40A and 40B. FIG. 40A is a schematicillustration of a multi-wavelength rotating disk, generally referenced1930, constructed and operative in accordance with a further embodimentof the disclosed technique. FIG. 40B is a schematic illustration of amulti-wavelength rotating disk, generally referenced 1950, constructedand operative in accordance with another embodiment of the disclosedtechnique.

With reference to FIG. 40A, multi-wavelength rotating disk 1930 isdivided to a transparent portion 1932 and an opaque portion 1934.Transparent portion 1932 and opaque portion 1934 are divided by adiameter 1936 of multi-wavelength rotating disk 1930. Transparentportion 1932 is divided to a plurality of filtering sectors 1938, 1940and 1942. Filtering sectors 1938, 1940 and 1942 occupy substantiallyequal areas. Each of the filtering sectors 1938, 1940 and 1942 admitslight at a different range of wavelengths (either in the visible rangeor the invisible range), while opaque portion 1934 blocks light at allof these different range of wavelengths. In the example set forth inFIG. 40A, filtering sectors 1938, 1940 and 1942 admit red, green andblue light, respectively.

With reference to FIG. 40B, multi-wavelength rotating disk 1950 includesa plurality of filtering sectors 1952, 1954 and 1956 and a plurality ofopaque sectors 1958, 1960 and 1962. Filtering sectors 1952, 1954 and1956, and opaque sectors 1958, 1960 and 1962, occupy substantially equalareas. Each of the filtering sectors 1952, 1954 and 1956 admits light ata different range of wavelengths (either in the visible range or theinvisible range), while opaque sectors 1958, 1960 and 1962 block lightat all of these different range of wavelengths. In the example set forthin FIG. 40B, filtering sectors 1952, 1954 and 1956 admit red, green andblue light, respectively.

According to another aspect of the disclosed technique, thetwo-dimensional light sensor array is replaced by a one-dimensionallight sensor array and a rotating mirror, which swivels about an axisperpendicular to the stereoscopic axis. The rotating mirror rotatesabout an axis which is parallel to the one-dimensional light sensorarray, thereby continuously scanning the surface of a three-dimensionalbody. The rotating mirror directs the scanned image to theone-dimensional light sensor array, via an image differentiator, a lightdirecting assembly and an optical assembly. A controller coupled withthe one-dimensional light sensor array enables the one-dimensional lightsensor array to detect images of different regions of thethree-dimensional object in sequence. The image differentiatordifferentiates between a line of the right side view image and a line ofthe left side view image of each of these different regions, beforethese lines of image reach the one-dimensional light sensor array.

Reference is now made to FIGS. 41A, 41B and 41C. FIG. 41A is a schematicillustration of a top view of a stereoscopic image scanning apparatus,generally referenced 2000, constructed and operative in accordance witha further embodiment of the disclosed technique. FIG. 41B is a schematicillustration of side view (referenced A in FIG. 41A) of the apparatus ofFIG. 41A, in one mode of scanning. FIG. 41C is a schematic illustrationof the apparatus of FIG. 41B, in another mode of scanning.

With reference to FIG. 41A, apparatus 2000 includes a scanning element2002, an image differentiator 2004, an image directing assembly 2006, anoptical assembly 2008 and an image detector 2010. Image differentiator2004 includes static polarizers 2012 and 2014, and a dynamic polarizer2016. Image directing assembly 2006 includes a right periscopic prism2018 and a left periscopic prism 2020. Image detector 2010 includes aone-dimensional light sensor array, which is essentially a plurality oflight sensors, arranged in a row. Scanning element 2002 can be in formof a flat mirror, prism, lens, spherical mirror, aspherical mirror,holographic element, and the like. In the examples described accordingto FIGS. 41B and 41C, scanning element 2002 is in form of a mirror.

Static polarizers 2012 and 2014 are located between scanning element2002 and image directing assembly 2006. Image directing assembly 2006 islocated between static polarizers 2012 and 2014 on one side and dynamicpolarizer 2016 on the other side. Dynamic polarizer 2016 is locatedbetween image directing assembly 2006 and optical assembly 2008. Opticalassembly 2008 is located between dynamic polarizer 2016 and imagedetector 2010.

With further reference to FIG. 41B, a three-dimensional object 2022 islocated at a side of apparatus 2000. In this configuration thelongitudinal axis of apparatus 2000 is approximately perpendicular tothe viewing direction of three-dimensional object 2022, by apparatus2000.

Scanning element 2002 being at a certain angular position, directs animage line of a region 2024 of three-dimensional object 2022, to staticpolarizers 2012 and 2014. Right periscopic prism 2018 receives a line ofthe right side view image of region 2024 via static polarizer 2012 andleft periscopic prism 2020 receives a line of the left side view imageof region 2024 via static polarizer 2014. Right periscopic prism 2018and left periscopic prism 2020 direct the line of the right side viewimage and the line of the left side view image of region 2024 to dynamicpolarizer 2016. In the example set forth in FIG. 41A, the polarizationangle of dynamic polarizer 2016 is substantially the same as thepolarization angle of static polarizer 2012. Hence, the light beamswhich define the line of the right side view image, pass through dynamicprism 2016 and enter optical assembly 2008. Optical assembly 2008directs the line of the right side view image on one-dimensional lightsensor array 2010. Since the polarization angle of dynamic polarizer2016 is approximately 90 degrees away from the polarization angle ofstatic polarizer 2014, dynamic polarizer 2016 blocks the light beamswhich define the line of the left side view image and the line of leftside view image does not reach one-dimensional light sensor array 2010.

With further reference to FIG. 41C, scanning element 2002 is at anotherangular position relative to the one illustrated in FIG. 41B. Hence,scanning element 2002 directs a line of an image of a region 2026 ofthree-dimensional object 2022, to static polarizers 2012 and 2014. Rightperiscopic prism 2018 and left periscopic prism 2020 receive a line of aright side view image and a line of a left side view image of the imageof region 2026, via static polarizers 2012 and 2014, respectively. Rightperiscopic prism 2018 and left periscopic prism 2020 direct the line ofthe right side view image and the line of the left side view image,respectively, to dynamic polarizer 2016. In the example set forth inFIG. 41A, the polarization angle of dynamic polarizer 2016 issubstantially the same as the polarization angle of static polarizer2012 and the polarization angle of dynamic polarizer 2016 isapproximately 90 degrees away from that of static polarizer 2014.

Hence, the light beams which define the line of the right side viewimage of region 2026 pass through dynamic polarizer 2016 and reachone-dimensional light sensor array 2010, while the light beams whichdefine the line of the left side view image of region 2026 are blockedby dynamic polarizer 2016 and do not reach one-dimensional light sensorarray 2010. A controller which is coupled with scanning element 2002 andto one-dimensional light sensor array 2010, enables one-dimensionallight sensor array 2010 to detect a line of an image ofthree-dimensional object 2022, according to the angular position ofscanning element 2002. It is noted that scanning element 2002 can eitherrotate continuously, or rotate back and forth between two angularpositions.

Alternatively, the image detector is a two-dimensional light sensorarray operating in time delay integration (TDI) mode. The scanningelement scans a plurality of successive two-dimensional regions of thethree-dimensional object. The scanning element directs thetwo-dimensional images of these two-dimensional regions, in succession,to the image detector. A controller is coupled with the scanning elementand to the image detector. The controller successively shifts theelectronic charges from one row of the image detector to the other rowin turn, along the columns of the image detector in synchrony with thescanning movement of the scanning element. After shifting the electroniccharges from a first row to a second row, the controller resets thefirst row. In this manner, the sum of the electronic charges of all therows are accumulated in the last row of the two-dimensional light sensorarray. The controller delivers the charges from the last row of theimage detector, in sequence and in synchrony with the scanning movementof the scanning element, to an image processor. The image processorproduces a substantially sharp stereoscopic image of the region of thethree-dimensional object, which the scanning element repeatedly scans.

It is noted, that if the image detector does not operate in TDI mode(i.e., the controller does not shift the charges from one column to theother), then the image processor produces a blurred stereoscopic imageof the three-dimensional object. This is so, because the scanningelement provides images of successive regions of the three-dimensionalobject to the image detector. The image processor produces astereoscopic image of the three-dimensional object and the stereoscopicimage is blurred according to the scanning speed of the scanningelement.

According to another aspect of the disclosed technique, a right sidefilter and a left side filter are employed, each admitting an image attwo different ranges of wavelengths. When the three-dimensional body issequentially illuminated with light at each of the first ranges ofwavelengths, the right side filter sequentially directs a right sideview image of the three-dimensional object to the image detector, ateach one of the first ranges of wavelengths. Likewise, when thethree-dimensional body is sequentially illuminated at each of the secondranges of wavelengths, the left side filter sequentially directs a leftside view image of the three-dimensional object to the image detector,at each one of the second ranges of wavelengths.

Reference is now made to FIGS. 42A and 42B. FIG. 42A is a schematicillustration of a stereoscopic imaging apparatus, generally referenced2040, constructed and operative in accordance with another embodiment ofthe disclosed technique. FIG. 42B is a schematic illustration of thestereoscopic imaging apparatus of FIG. 42A, in another mode ofoperation.

Apparatus 2040 includes a right side filter 2042, a left side filter2044, an image detector 2046, an illuminator 2048, a controller 2050, astorage unit 2052 and an image processor 2054. Right side filter 2042and left side filter 2044 are located between a three-dimensional object2056 and image detector 2046. Controller 2050 is coupled withilluminator 2048. Image detector 2046 controller 2050, storage unit 2052and image processor 2054 are coupled together via a bus 2058.

Right side filter 2042 admits light within the ranges of wavelengthsΔR₁, ΔG₁ and ΔB₁. Left side filter 2044 admits light within the rangesof wavelengths ΔR₂, ΔG₂ and ΔB₂. Illuminator 2048 sequentially emitslight at each of the ranges of wavelengths ΔR₁, ΔG₁, ΔB₁, ΔR₂, ΔG₂ andΔB₂.

With reference to FIG. 42A, illuminator 2048 sequentially emits light ateach of the ranges of wavelengths ΔR₁, ΔG₁ and ΔB₁. Right side filter2042 sequentially directs right side view images 2048 ^(R) _(R), 2048^(R) _(G) and 2048 ^(R) _(B) in red, green and blue, respectively, toimage detector 2046 and controller 2050 enables image detector 2046 todetect these images in sequence. Controller 2050 stores these images instorage unit 2052. Image processor 2054 produces a video signalrespective of a full color right side view image of three-dimensionalobject 2056, by retrieving right side view images 2048 ^(R) _(R), 2048^(R) _(G) and 2048 ^(R) _(B) from storage unit 2052 and processing theseimages. Since left side filter 2044 admits light only within the rangesof wavelengths ΔR₂, ΔG₂ and ΔB₂, left side filter 2044 does not directthe left side view image of three-dimensional object 2056 to imagedetector 2046.

With reference to FIG. 42B, illuminator 2048 sequentially provides lightat each of the ranges of wavelengths ΔR₂, ΔG₂ and ΔB₂. In this case,left side filter 2044 sequentially directs left side view images 2048^(L) _(R), 2048 ^(L) _(G) and 2048 ^(L) _(B) in red, green and blue,respectively, to image detector 2046 and controller 2050 enables imagedetector 2046 to detect these images in sequence. Controller 2050 storesthese images in storage unit 2052. Image processor 2054 produces a videosignal respective of a full color left side view image ofthree-dimensional object 2056, by retrieving left side view images 2048^(L) _(R), 2048 ^(L) _(G) and 2048 ^(L) _(B) from storage unit 2052 andprocessing these images. Since right side filter 2042 admits light onlywithin the ranges of wavelengths ΔR₁, ΔG₁ and ΔB₁, right side filter2042 does not direct the right side view image of three-dimensionalobject 2056 to image detector 2046.

Alternatively, illuminator 2048 is replaced by a sequentialmulti-wavelength illuminator which emits light at a mixture of theranges of wavelengths ΔR₁, ΔG₁ and ΔB₁ and at a mixture of the ranges ofwavelengths ΔR₂, ΔG₂ and ΔB₂. The sequential multi-wavelengthilluminator sequentially emits light at each of the mixtures of theranges of wavelengths ΔR₁, ΔG₁ and ΔB₁, and at each of the mixtures ofthe ranges of wavelengths ΔR₂, ΔG₂ and ΔB₂. When the sequentialmulti-wavelength illuminator emits light at the mixture of the ranges ofwavelengths ΔR₁, ΔG₁ and ΔB₁, right side filter 2042 directs a fullcolor right side view image of three-dimensional object 2056, at themixture of the ranges of wavelengths ΔR₁, ΔG₁ and ΔB₁, to image detector2046. When the sequential multi-wavelength illuminator emits light atthe mixture of the ranges of wavelengths ΔR₂, ΔG₂ and ΔB₂, left sidefilter 2044 directs a full color left side view image ofthree-dimensional object 2056, at the mixture of the ranges ofwavelengths ΔR₂, ΔG₂ and ΔB₂, to image detector 2046.

Further alternatively, illuminator 2048 is replaced by amulti-wavelength illuminator which emits light at a range of wavelengthswhich encompasses the ranges of wavelengths ΔR₁, ΔG₁, ΔB₁, ΔR₂, ΔG₂ andΔB₂ and a duo-tone rotating disk in located between the right sidefilter and the left side filter at one side and the image detector atthe other. The duo-tone rotating disk is divided to two transparentportions. One transparent portion of the duo-tone rotating disk admitslight at the ranges of wavelengths ΔR₁, ΔG₁ and ΔB₁, and the othertransparent portion thereof, admits light at the ranges of wavelengthsΔR₂, ΔG₂ and ΔB₂. The multi-wavelength illuminator continuouslyilluminates the three-dimensional object. As the duo-tone rotating diskrotates, the right side filter and the left side filter sequentiallydirect a full color right side view image and a full color left sideview image, respectively, of the three-dimensional object, to the imagedetector.

Alternatively, right side filter 2042 and left side filter 2044 arespaced apart. In this case right side filter 2042 receives a right sideview image of three-dimensional object 2056, which is considerably moredistinct than a left side view image thereof, thereby allowing imageprocessor 2054 to produce a more realistic full color stereoscopic imageof three-dimensional object 2056. It is noted that instead of theduo-tone rotating disk, other types of rotating disks can be employed,such as a multi-wavelength rotating disk (FIGS. 40A and 40B), definedaccording to ΔR₁, ΔG₁, ΔB₁, ΔR₂, ΔG₂ and ΔB₂.

Reference is now made to FIG. 43, which is a schematic illustration of amethod for operating a stereoscopic imaging apparatus, operative inaccordance with a further embodiment of the disclosed technique. Inprocedure 2080, a plurality of first ranges of filter wavelengths and aplurality of second ranges of filter wavelengths are determined for afirst pupil and a second pupil, respectively. With reference to FIG.30A, right side filter 1202 admits light at the ranges of wavelengthsΔR₁, ΔG₁, and ΔB₁ and left side filter 1204 admits light at the rangesof wavelengths ΔR₁, ΔG₁, and ΔB₁.

In procedure 2082, a first set of differentiating wavelengths which isincluded in the first ranges of filter wavelengths and excluded from thesecond ranges of filter wavelengths, is determined. With reference toFIG. 30A, illuminating unit 1240 is associated with the group ofwavelengths RGB₁ which is included in the ranges of wavelengths ΔR₁,ΔG₁, and ΔB₁ and excluded from the ranges of wavelengths ΔR₂, ΔG₂, andΔB₂. In procedure 2082, a second set of differentiating wavelengths,which is included in the second ranges of filter wavelengths andexcluded from the first ranges of filter wavelengths, is determined.With reference to FIG. 30A, illuminating unit 1240 is associated withthe group of wavelengths RGB₂ which is included in the ranges ofwavelengths ΔR₂, ΔG₂, and ΔB₂ and excluded from the ranges ofwavelengths ΔR₁, ΔG₁, and ΔB₁.

In procedure 2086, an object is sequentially illuminated with the firstset of differentiating wavelengths and with the second set ofdifferentiating wavelengths. With reference to FIGS. 30A and 30B,illuminating unit 1240 sequentially illuminates three-dimensional object1230 at the group of wavelengths RGB₁ and at the group of wavelengthsRGB₁.

In procedure 2088, a first image is detected when the first set ofdifferentiating wavelengths is present and a second image is detectedwhen the second set of differentiating wavelengths is present. Withreference to FIG. 30A, controller 1216 enables light sensor array 1210to detect the right side view image of three-dimensional object 1230,when illuminating unit 1240 emits light at the group of wavelengthsRGB₁. With reference to FIG. 30B, controller 1216 enables light sensorarray 1210 to detect the left side view image of three-dimensionalobject 1230, when illuminating unit 1240 emits light at the group ofwavelengths RGB₂.

According to another embodiment, differentiation is performed bysequentially admitting light at the different sets of wavelengths, by asequential filtering device, such as a rotating disk, an alternatingfilter, and the like. According to this embodiment, procedure 2090replaces procedure 2086. In procedure 2090, light is admittedsequentially at the first set of differentiating wavelengths and at thesecond set of differentiating wavelengths.

The light differentiator can be any optical device which candifferentiate between different wavelengths (e.g., by means ofillumination, reflection or filtration). For example, the lightdifferentiator can be a rotating disk divided into filtering sectors,wherein each filtering sector filters light at wavelengths which areincluded in one of the right side filter and the left side filter andexcluded from the other of these two filters. Alternatively, areflective rotating disk can be employed, which is divided into aplurality of reflecting sectors, where each reflecting sector reflectslight at a different wavelength. Further alternatively, a multi-stateflipping filter can be employed, which is mechanically flipped from onelight filter to the other, in sequence. Other types of sequentialfilters, such as those which are operated electrically rather thanmechanically, are applicable to this embodiment. Alternatively, thelight differentiator can be a set of partially reflective mirrors thatcan be operated sequentially, each reflecting light at wavelengths whichare included in one of the right side filter and the left side filterand excluded from the other of these two filters (e.g., a partiallyreflective mirror which reflects light at CYMG₁ and another partiallyreflective mirror which reflects light at CYMG₂).

Reference is further made to FIGS. 44A and 44B. FIG. 44A is a schematicillustration of a rotating disk, generally referenced 2100, constructedand operative in accordance with another embodiment of the disclosedtechnique. FIG. 44B is a schematic illustration of a rotating disk,generally referenced 2110, constructed and operative in accordance witha further embodiment of the disclosed technique.

With reference to FIG. 44A, rotating disk 2100 includes two filteringsectors 2102 and 2104, and two opaque sectors 2106 and 2108. Filteringsector 2102 admits light at a group of wavelengths R₁, G₁ and B₁ (i.e.,RGB₁), whereas filtering sector 2104 admits light at a group ofwavelengths R₂, G₂ and B₂ (i.e., RGB₂). With reference to FIG. 44B,rotating disk 2110 includes filtering sectors 2112, 2114, 2116, 2118,2120 and 2122, which admit light at wavelengths R₁, G₁, B₁, R₂, G₂ andB₂, respectively.

In examples described above, the light differentiator differentiatesbetween two groups of wavelengths, where each group of wavelengthsincludes three wavelengths (i.e., R, G and B). Thus, the lightdifferentiator of the stereoscopic imaging apparatus differentiatesbetween two red wavelengths (R₁ and R₂), two green wavelengths (G₁ andG₂) and two blue wavelengths (B₁ and B₂). As noted above, the lightdifferentiator can be for example, an illuminator, a light filteringelement or a light reflecting element.

However, it is noted that each of the two groups of wavelengths caninclude more than three wavelengths and for that matter, any number ofwavelengths. For example, high quality spectrometers are capable tosplit the light to 20 or 40 or more different wavelengths (e.g., IR₁,IR₂, IR₃, IR₄, . . . IR_(n), R₁, R₂, R₃, . . . , R_(m), G₁, G₂, G₃, . .. G_(p), B₁, B₂, B₃, . . . , B_(q), UV₁, UV₂, UV₃, . . . , UV_(S), andthe like).

Reference is now made to FIGS. 45A and 45B. FIG. 45A is a schematicillustration of a stereoscopic imaging apparatus, generally referenced2140, constructed and operative in accordance with another embodiment ofthe disclosed technique. FIG. 45B is a schematic illustration of a topview of the apparatus of FIG. 45A.

With reference to FIG. 45A, apparatus 2140 includes a periscope assembly2142, an image differentiator 2144, an optical assembly 2146 and a lightsensor array 2148. Periscope assembly 2142 includes a right front mirror2150, a left front mirror 2152, a right middle mirror 2154, a leftmiddle mirror 2156, a right rear mirror 2158 and a left rear mirror2160. In the example set forth in FIG. 45A, image differentiator 2144 isa multiple aperture similar to multiple aperture 1154 (FIG. 29A). Imagedifferentiator 2144 includes a right aperture 2162 and a left aperture2164.

Periscope assembly 2142 is located between a three-dimensional object2166 and image differentiator 2144. Image differentiator 2144 is locatedbetween periscope assembly 2142 and optical assembly 2146. Opticalassembly 2146 is located between image differentiator 2144 and lightsensor array 2148.

The X axis designates the longitudinal axis of apparatus 2140. The Xaxis together with the Y and Z axes, form a rectilinear coordinatesystem. In the following description, the right hand rule applies tothis coordinate system. For example, the phrase “a tilt of positive 45degrees about the Z axis”, means a tilt of 45 degrees about the Z axisin the direction of the fingers, when the thumb points in the directionof the Z axis. On the other hand, the phrase “a tilt of negative 45degrees about the Z axis”, means a tilt of 45 degrees about the Z axisin the direction of the fingers, when the thumb points in a directionopposite to the Z axis.

The reflecting surface of right front mirror 2150 is tilted bypreferably positive 45 degrees about the Y axis from the Z-Y plane andby preferably negative 30 degrees about the Z axis, from the Z-X plane.The reflecting surface of left front mirror 2152 is tilted by preferablypositive 45 degrees about the Y axis from the X-Y plane and bypreferably negative 30 degrees about the Z axis, from the Z-X plane.

The reflecting surface of right middle mirror 2154 is tilted bypreferably negative 45 degrees about the X axis from the Z-X plane andby preferably negative 30 degrees about the Z axis, from the Z-X plane.The reflecting surface of left middle mirror 2156 is tilted bypreferably positive 45 degrees about the X axis from the Z-X plane andby preferably negative 30 degrees about the Z axis, from the Z-X plane.

The reflecting surfaces of right rear mirror 2158 and left rear mirror2160 are tilted by preferably negative 60 degrees about the Z axis fromthe Z-X plane. Hence, periscope assembly 2142 is tilted preferably bynegative 30 degrees about the Z axis from the Z-X plane.

Right front mirror 2150 receives a light beam 2168 respective of a rightside view image of three-dimensional object 2166. Since periscopeassembly 2142 is tilted by substantially negative 30 degrees about the Zaxis, light beam 2168 is located on a plane which is tilted bysubstantially negative 30 degrees from the Z-X plane, about the Z axis.Right front mirror 2150 directs a reflection of light beam 2168 towardright middle mirror 2154, as a light beam 2170. Light beam 2170 islocated on the Z-X plane.

Right middle mirror 2154 directs a reflection of light beam 2170 towardright rear mirror 2158, as a light beam 2172. Light beam 2172 is locatedat the intersection of the X-Y plane and a plane which is tilted aboutthe Z axis by approximately positive 60 degrees from the Z-X plane.Right rear mirror 2158 directs a reflection of light beam 2172 towardimage differentiator 2144, as a light beam 2174. Light beam 2174 pointsin a direction substantially parallel to the X axis. In the example setforth in FIG. 45A, right aperture 2162 is open while left aperture 2164is closed. Thus, image differentiator 2144 admits light beam 2174 andoptical assembly 2146 directs light beam 2174 toward light sensor array2148.

With reference to FIG. 45B, right front mirror 2150 receives light beam2168 at an angle of approximately 30 degrees relative to the X axis.Right middle mirror 2154 reflects light beam 2168 as light beam 2170(not shown in FIG. 45B) in a direction pointing into the drawing andright middle mirror 2154 reflects light beam 2170 as light beam 2172. Asshown in FIG. 45B, light beam 2172 points in a direction ofapproximately 90 degrees relative to that of light beam 2168. Right rearmirror 2158 is tilted approximately 60 degrees relative to the X axis,whereby right rear mirror 2158 reflects light beam 2172 as light beam2174 in a direction substantially parallel to the X axis.

Referring back to FIG. 45A, left front mirror 2152 receives a light beam2176 respective of a left side view image of three-dimensional object2166 and directs a reflection of light beam 2176 toward left middlemirror 2156, as a light beam 2178. Light beam 2176 is located on thesame plane as that of light beam 2168 and light beam 2178 is located onthe same plane as that of light beam 2170. Left middle mirror 2156directs a reflection of light beam 2178 toward left rear mirror 2160, asa light beam 2180. Light beam 2180 is located on the same plane as thatof light beam 2172. Left rear mirror directs a reflection of light beam2180 toward image differentiator 2144, as a light beam 2182. Light beam2182 points in a direction substantially parallel to the X axis. Sinceleft aperture 2164 is closed, image differentiator 2144 blocks lightbeam 2182.

It is noted that right front mirror 2150, right middle mirror 2154 andright rear mirror 2158 can be incorporated in a right prism, wherein theright prism is titled sideways relative to the longitudinal axis of theapparatus. In this case, each of the right front mirror 2150, rightmiddle mirror 2154 and right rear mirror 2158 represents the respectivereflective surface of the right prism. Likewise, right front mirror2152, right middle mirror 2156 and right rear mirror 2160 can beincorporated in a left prism, wherein the left prism is titled sidewaysrelative to the longitudinal axis of the apparatus, by the same amountas the right prism. Thus, the right prism receives a right side viewimage of a three-dimensional object which is located at a side of theapparatus, while the left prism receives a left side view image of thethree-dimensional.

It is noted that above optical structure provides a clear, straight andundistorted image at each of the right and left channels.

Reference is now made to FIG. 46A and FIG. 46B. FIG. 46A is a schematicillustration of a physical object 2202 and a stereoscopic imagingapparatus, generally referenced 2200, constructed and operative inaccordance with a further embodiment of the disclosed technique. FIG.46B is a schematic illustration of the apparatus of FIG. 46A, with adifferent set of light rays shown.

With reference to FIG. 46A, apparatus 2200 includes an objective lensassembly 2204, a lenticular lens layer 2206 and a light sensor array2208. Lenticular lens layer 2206 and light sensor array 2208 aregenerally similar to lenticular lens layer 1106 and light sensor array1108 of FIG. 28A. Objective lens assembly 2204 includes an aperture stop2210, including a left pupil P_(L) and a right pupil P_(R). Aperturestop 2210 transmits light incident upon left pupil P_(L) and a rightpupil P_(R), and substantially reflects or absorbs all other incidentlight.

Objective lens assembly 2204 generates two overlapping images on theimage plane (i.e., on the plane defined by the light sensor array 2208).One of these images arrives from left pupil P_(L) and the other imagearrives from right pupil P_(R). With reference to FIG. 46A, objectivelens assembly 2204 receives light beams 2220A, 2222A and 2224A fromphysical object 2202, at left pupil P_(L). Objective lens assembly 2204emits light beams 2220A, 2222A and 2224A as light beams 2220B, 2222B and2224B, respectively. Objective lens assembly 2204 directs light beams2220B, 2222B and 2224B towards lenticular lenses 2212 ₁, 2212 ₂ and 2212₃ of lenticular lens array 2206, respectively. Lenticular lenses 2212 ₁,2212 ₂ and 2212 ₃ direct light beams 2220B, 2222B and 2224B towardslight sensors 2214A_(L), 2214B_(L) and 2214C_(L), respectively, in asimilar manner as described in FIG. 28A.

Similarly, referring to FIG. 46B, objective lens assembly 2204 receiveslight beams 2270A, 2272A and 2274A from physical object 2202, at rightpupil P_(R). Light beams 2270A, 2272A and 2274A originate from the samepoints on physical object 2202 as light beams 2220A, 2222A and 2224A,respectively. Objective lens assembly 2204 emits light beams 2270A,2272A and 2274A as light beams 2270B, 2272B and 2274B, respectively.Light beams 2270B, 2272B and 2274B are emitted at a substantiallyopposite direction, relative to an axis perpendicular to the imageplane, from light beams 2220B, 2222B and 2224B (FIG. 46A). Light beams2270B, 2272B and 2274B reach lenticular elements 2214A_(R), 2214B_(R)and 2214C_(R), respectively. Lenticular lenses 2212 ₁, 2212 ₂ and 2212 ₃direct light beams 2270B, 2272B and 2274B towards light sensors2214A_(R), 2214B_(R) and 2214C_(R), respectively.

It is noted that in the present example, objective lens assembly 2204 istelecentric. Accordingly, light beams 2270B, 2272B and 2274B areparallel there between, as are light beams 2220B, 2222B and 2224B.Hence, each lenticular lens receives light beams at one of two specificdirections, and directs these light beams to one of two specific lightsensors. Alternatively, the objective lens assembly may be nearlytelecentric, in which case these light beams are only approximatelyparallel, but the lenticular lens still separates between the two groupsof light beams. In general, the objective lens assembly should directthe light beams from the left pupil in a direction from a first set ofdirections, and the light beams from the right pupil in a direction froma second set of directions.

According to the present embodiment, the pupils P_(L) and P_(R) definethe “eyes” of the optical device, which are required for stereoscopicvision. It is noted that the light beams arrive at the lenticularelements substantially in one of two specific directions. Hence, eachlenticular element distinguishes precisely between the light receivedfrom the left pupil and that received from the right pupil.

Alternatively, the aperture stop includes “soft” pupils, instead of thepupils P_(L) and P_(R). Reference is now made to FIG. 47, which is aschematic illustration of an aperture stop, generally referenced 2300,constructed and operative in accordance with another embodiment of thedisclosed technique. Aperture stop 2300 includes a left soft pupilP_(L(S)) and a right soft pupil P_(R(S)). Each of pupils P_(L(S)) andP_(R(S)) are in the form of a dent (instead of an aperture as in thecase of ordinary “hard” pupils) in aperture stop 2300. Hence, theaperture stop is thinner at the soft pupils than at is at the rest ofthe plane, and therefore transmits more light at the pupils than at therest of the plane. The light transmission through aperture stop 2300 isspatially variable, but not binary as in the case of “hard pupils”.

Further alternatively, the left and right pupils may be “virtualpupils”. Accordingly, the plane of aperture stop 2210 (FIG. 46A)transmits light there through at different locations thereon. Thetransmitted light reaches a lenticular lens array. Each lenticular lensreceives light beams from various locations on the plane, and directseach of these light beams accordingly towards a light sensor array.However, only those light beams which are incident from two specificlocations on the plane, namely, the left virtual pupil and the rightvirtual pupil, are taken into account in forming the stereoscopic image.For example, some of the light sensors, which receive light beamsincident from other locations on the plane, may be removed, replaced, orignored. Furthermore, the light sensors may be given different weightsaccording to the certainty as to the location on the plane of therespective incident light beams.

It will be appreciated by persons skilled in the art that the disclosedtechnique is not limited to what has been particularly shown anddescribed here in above. Rather the scope of the disclosed technique isdefined only by the claims which follow.

1. Stereoscopic device, comprising: an image directing assembly, havinga first light inlet for receiving a first image and a second light inletfor receiving a second image, said first light inlet being spaced apartfrom said second light inlet; an image differentiator, differentiatingbetween said first image and said second image, said imagedifferentiator having a first state and a second state; an imagedetector, wherein said image directing assembly directs said first imageto said image detector via a common path, wherein said image directingassembly directs said second image to said image detector via saidcommon path; an optical assembly located in front of said imagedetector; and a controller coupled with said image detector and withsaid image differentiator, said controller controlling the state of saidimage differentiator, said controller enabling said image detector todetect said first image when said image differentiator is in said firststate and said controller enabling said image detector to detect saidsecond image when said image differentiator is in said second state. 2.The stereoscopic device according to claim 1, wherein said imagedifferentiator is a partially-transparent rotating disk located wheresaid first image and said second image are two distinct images, in frontof said common path, wherein said partially-transparent rotating diskhas a transparent portion and an opaque portion, wherein saidpartially-transparent rotating disk admits said first image through saidtransparent portion when said partially-transparent rotating diskrotates to a first position, corresponding to said first state of saidimage differentiator, and said partially-transparent rotating diskadmits said second image through said transparent portion when saidpartially-transparent rotating disk rotates to a second position,corresponding to said second state of said image differentiator.
 3. Thestereoscopic device according to claim 2, further comprising anilluminator which emits light at a predetermined illuminatingwavelength.
 4. The stereoscopic device according to claim 3, whereinsaid predetermined illuminating wavelength is selected from the listconsisting of: substantially visible red color light; substantiallyvisible green color light; substantially visible blue color light;substantially visible cyan color light; substantially visible yellowcolor light; substantially visible magenta color light; substantiallyinfra-red light; substantially ultra-violet light; and visible light. 5.The stereoscopic device according to claim 2, further comprising anilluminator which sequentially emits light at different predeterminedilluminating wavelengths, said illuminator coupled with said controller,wherein said controller controls the operation of said illuminator,wherein said controller enables said image detector to detect said firstimage at each one of said different predetermined illuminatingwavelengths, and said second image at each one of said differentpredetermined illuminating wavelengths, according to the angularposition of said partially-transparent rotating disk and according tothe state of said illuminator.
 6. The stereoscopic device according toclaim 5, wherein each of said different predetermined illuminatingwavelengths is selected from the list consisting of: substantiallyvisible red color light; substantially visible green color light;substantially visible blue color light; substantially visible cyan colorlight; substantially visible yellow color light; substantially visiblemagenta color light; substantially infra-red light; substantiallyultra-violet light; and visible light.
 7. The stereoscopic deviceaccording to claim 1, wherein said image differentiator is amulti-wavelength rotating disk located where said first image and saidsecond image are two distinct images, in front of said common path, saidmulti-wavelength rotating disk comprises a plurality of filteringsectors, wherein each of said filtering sectors admits light in adifferent predetermined range of filter wavelengths, each angularposition of said multi-wavelength rotating disk corresponding to aselected one of said first state and said second state of said imagedifferentiator, and wherein said controller enables said image detectorto detect said first image and said second image at each one of saiddifferent predetermined ranges of filter wavelengths, according to theangular position of said multi-wavelength rotating disk.
 8. Thestereoscopic device according to claim 7, wherein said multi-wavelengthrotating disk further comprises at least one opaque sector.
 9. Thestereoscopic device according to claim 7, further comprising anilluminator.
 10. The stereoscopic device according to claim 1, whereinsaid image differentiator is located where said first image and saidsecond image are two distinct images, in front of said common path,wherein said image differentiator is a multiple aperture having a firstaperture and a second aperture, wherein an opening of said firstaperture corresponds to said first state of said image differentiatorand an opening of said second aperture corresponds to said second stateof said image differentiator, wherein said controller alternatelycontrols the opening of said first aperture and said second aperture, tocontrol the state of said image differentiator.
 11. The stereoscopicdevice according to claim 10, further comprising an illuminator whichsequentially emits light at different predetermined illuminatingwavelengths, wherein said controller enables said image detector todetect images, corresponding to a predetermined combination of an openstate of a selected aperture of said multiple aperture and a selectedone of said different predetermined illuminating wavelengths.
 12. Thestereoscopic device according to claim 1, wherein said controller isfurther coupled with said image differentiator, said imagedifferentiator comprising: a first polarizer located in the path of saidfirst image, before said common path; a second polarizer located in thepath of said second image, before said common path; and a thirdpolarizer located in front of said image detector, wherein similarpolarization angle of said first polarizer and said third polarizercorresponds to said first state of said image differentiator, andsimilar polarization angle of said second polarizer and said thirdpolarizer corresponds to said second state of said image differentiator,wherein said controller controls the polarization angle of at least oneof said first polarizer, said second polarizer and said third polarizer,to control the state of said image differentiator.
 13. The stereoscopicdevice according to claim 12, wherein said first polarizer and saidsecond polarizer are static and said third polarizer is dynamic.
 14. Thestereoscopic device according to claim 12, wherein said first polarizerand said second polarizer are dynamic and said third polarizer isstatic.
 15. The stereoscopic device according to claim 12, wherein saidfirst polarizer and said second polarizer are located on a rotatingdisk.
 16. The stereoscopic device according to claim 12, wherein saidimage differentiator further comprises at least one polarizationrotating cell.
 17. The stereoscopic device according to claim 1, whereinsaid image differentiator is a lenticular lens layer, including aplurality of lenticular elements, located in front of said imagedetector, wherein said lenticular elements enable said lenticular lenslayer to differentiate between said first image and said second image,wherein said lenticular lens layer directs said first image and saidsecond image to said image detector, and wherein said controller enablessaid image detector to detect said first image and said second image.18. The stereoscopic device according to claim 1, wherein said imagedirecting assembly further comprises: a first mirror for receiving saidfirst image; a second mirror for receiving said second image; a firstcenter mirror for directing said first image from said first mirror tosaid common path; and a second center mirror for directing said secondimage from said second mirror to said common path.
 19. The stereoscopicdevice according to claim 1, said image directing assembly comprising: afirst parallelogramic prism for directing said first image to saidcommon path; and a second parallelogramic prism for directing saidsecond image to said common path.
 20. The stereoscopic device accordingto claim 19, further comprising: a rail; and a hinge sliding in saidrail, wherein said first parallelogramic prism and said secondparallelogramic prism are coupled with said hinge, wherein said firstparallelogramic prism and said second parallelogramic prism move from aretracted position to an extended position, by rotating about said hingewhen said hinge moves within said rail.
 21. The stereoscopic deviceaccording to claim 1, said image directing assembly comprising: a firstfiberscope located between said first light inlet and said common path,said first fiberscope having a first light outlet; and a secondfiberscope located between said second light inlet and said common path,said second fiberscope having a second light outlet, wherein said firstfiberscope directs said first image from said first light inlet to saidfirst light outlet, wherein said second fiberscope directs said secondimage from said second light inlet to said second light outlet.
 22. Thestereoscopic device according to claim 1, said image directing assemblycomprising: a plurality of split fibers located between said first lightinlet, said second light inlet and said common path, said split fibershaving a light outlet, each said split fibers having a first arm, asecond arm and a common arm, wherein said first arms direct said firstimage from said first light inlet to said common path via said lightoutlet, wherein said second arms direct said second image from saidsecond light inlet to said common path via said light outlet.
 23. Thestereoscopic device according to claim 1, wherein said image detectorcomprises: a one-dimensional light sensor array; and a scanner, whereinsaid scanner scans an object and directs a plurality of lines of animage of said object to said one-dimensional light sensor array, whereinsaid controller is further coupled with said scanner, and wherein saidcontroller enables said one-dimensional light sensor array to detecteach of said lines, according to the angular position of said scanner.24. The stereoscopic device according to claim 1, wherein said imagedetector comprises: a two-dimensional light sensor array; and a scanner,wherein said scanner scans an object and directs a plurality oftwo-dimensional images of said object to said two-dimensional lightsensor array, wherein said controller is further coupled with saidscanner, wherein said controller controls the operation of saidtwo-dimensional light sensor array in a time delay integration mode, andwherein said controller enables said two-dimensional light sensor arrayto detect said two-dimensional images, according to the angular positionof said scanner.